diff --git a/typed-racket-lib/typed-racket/optimizer/pair.rkt b/typed-racket-lib/typed-racket/optimizer/pair.rkt
index 0f90ec81..a5f97a30 100644
--- a/typed-racket-lib/typed-racket/optimizer/pair.rkt
+++ b/typed-racket-lib/typed-racket/optimizer/pair.rkt
@@ -6,7 +6,7 @@
          (for-syntax racket/base syntax/parse racket/syntax)
          "../utils/utils.rkt"
          (rep type-rep)
-         (types type-table utils base-abbrev)
+         (types type-table utils base-abbrev resolve subtype)
          (typecheck typechecker)
          (optimizer utils logging))
 
@@ -25,10 +25,7 @@
 
 
 (define (has-pair-type? e)
-  (and (subtypeof? e (-pair Univ Univ))
-       ;; sometimes composite operations end up with Nothing as result type,
-       ;; not sure why. TODO investigate
-       (not (isoftype? e -Bottom))))
+  (subtypeof? e (-pair Univ Univ)))
 ;; can't do the above for mpairs, as they are invariant
 (define (has-mpair-type? e)
   (match (type-of e) ; type of the operand
@@ -67,25 +64,12 @@
 
 
 ;; change the source location of a given syntax object
-(define (relocate stx loc-stx)
+(define ((relocate loc-stx) stx)
   (datum->syntax stx (syntax->datum stx) loc-stx stx stx))
 
 ;; if the equivalent sequence of cars and cdrs is guaranteed not to fail,
 ;; we can optimize
 
-;; accessors is a list of syntax objects, all #'car or #'cdr
-(define (gen-alt accessors op arg stx)
-  (define (gen-alt-helper accessors)
-    (for/fold [(accum arg)] [(acc (reverse accessors))]
-      (quasisyntax/loc stx (#%plain-app #,(relocate acc op) #,accum))))
-  (let ((ty  (type-of stx))
-        (obj (gen-alt-helper accessors)))
-    ;; we're calling the typechecker, but this is just a shortcut, we're
-    ;; still conceptually single pass (we're not iterating). we could get
-    ;; the same result by statically destructing the types.
-    (tc-expr/check obj ty)
-    obj))
-
 (define-syntax gen-pair-derived-expr
   (syntax-parser
     [(_ name:id (orig:id seq ...) ...)
@@ -96,8 +80,9 @@
            (define-literal-syntax-class lit-class-name (orig))
            (define-syntax-class syntax-class-name
              #:commit
+             #:attributes (arg alt)
              (pattern (#%plain-app (~var op lit-class-name) arg)
-               #:with alt (gen-alt (list seq ...) #'op #'arg this-syntax)))) ...
+               #:with alt (map (relocate #'op) (list seq ...))))) ...
          (define-merged-syntax-class name (syntax-class-name ...)))]))
 
 (gen-pair-derived-expr pair-derived-expr
@@ -144,5 +129,30 @@
 (define-syntax-class pair-derived-opt-expr
   #:commit
   (pattern e:pair-derived-expr
-           #:with e*:pair-opt-expr #'e.alt
-           #:with opt #'e*.opt))
+    #:with opt
+    ;; optimize alt inside-out, as long as it's safe to
+    (let-values
+        ([(t res)
+          (for/fold ([t   (match (type-of #'e.arg)
+                            [(tc-result1: t) t])]
+                     [res #'e.arg])
+              ([accessor (in-list (reverse (syntax->list #'e.alt)))])
+            (cond
+             [(subtype t (-pair Univ Univ)) ; safe to optimize this one layer
+              (syntax-parse accessor
+                [op:pair-op
+                 (log-pair-opt)
+                 (values
+                  (match (resolve t)
+                    [(Pair: a d) ; peel off one layer of the type
+                     (syntax-parse #'op
+                       [:car^ a]
+                       [:cdr^ d])]
+                    [_ ; not a pair type, give up on optimizing more
+                     #f])
+                  #`(op.unsafe #,res))])]
+             [else ; unsafe, just rebuild the rest of the accessors
+              (log-pair-missed-opt accessor #'e.arg)
+              (values t ; stays unsafe from now on
+                      #`(#,accessor #,res))]))])
+      res)))
diff --git a/typed-racket-test/optimizer/tests/derived-pair-open-terms.rkt b/typed-racket-test/optimizer/tests/derived-pair-open-terms.rkt
new file mode 100644
index 00000000..221743d0
--- /dev/null
+++ b/typed-racket-test/optimizer/tests/derived-pair-open-terms.rkt
@@ -0,0 +1,36 @@
+#;#;
+#<<END
+TR missed opt: derived-pair-open-terms.rkt 12:3 first -- car/cdr on a potentially empty list -- caused by: 12:9 x
+TR missed opt: derived-pair-open-terms.rkt 16:3 rest -- car/cdr on a potentially empty list -- caused by: 16:8 x
+TR missed opt: derived-pair-open-terms.rkt 20:3 cddr -- car/cdr on a potentially empty list -- caused by: 20:8 x
+TR opt: derived-pair-open-terms.rkt 20:3 cddr -- pair
+TR opt: derived-pair-open-terms.rkt 4:3 cadr -- pair
+TR opt: derived-pair-open-terms.rkt 4:3 cadr -- pair
+TR opt: derived-pair-open-terms.rkt 8:3 caddr -- pair
+TR opt: derived-pair-open-terms.rkt 8:3 caddr -- pair
+TR opt: derived-pair-open-terms.rkt 8:3 caddr -- pair
+END
+""
+
+#lang typed/racket #:optimize
+#reader typed-racket-test/optimizer/reset-port
+
+(: f ((List Integer Integer Integer) -> Integer))
+(define (f x)
+  (cadr x))
+
+(: g ((List Integer Integer Integer) -> Integer))
+(define (g x)
+  (caddr x))
+
+(: h ((Listof Integer) -> Integer))
+(define (h x)
+  (first x)) ; unsafe
+
+(: i ((Listof Integer) -> (Listof Integer)))
+(define (i x)
+  (rest x)) ; unsafe
+
+(: j ((cons Integer (Listof Integer)) -> (Listof Integer)))
+(define (j x)
+  (cddr x)) ; partially safe
diff --git a/typed-racket-test/optimizer/tests/derived-pair.rkt b/typed-racket-test/optimizer/tests/derived-pair.rkt
index d139d6ab..c04a2ccc 100644
--- a/typed-racket-test/optimizer/tests/derived-pair.rkt
+++ b/typed-racket-test/optimizer/tests/derived-pair.rkt
@@ -1,13 +1,13 @@
 #;#;
 #<<END
-TR opt: derived-pair.rkt 2:0 (caar (cons (cons 1 2) 3)) -- pair
-TR opt: derived-pair.rkt 2:0 (caar (cons (cons 1 2) 3)) -- pair
-TR opt: derived-pair.rkt 3:0 (cadr (cons 1 (cons 2 3))) -- pair
-TR opt: derived-pair.rkt 3:0 (cadr (cons 1 (cons 2 3))) -- pair
-TR opt: derived-pair.rkt 4:0 (cdar (cons (cons 1 2) 3)) -- pair
-TR opt: derived-pair.rkt 4:0 (cdar (cons (cons 1 2) 3)) -- pair
-TR opt: derived-pair.rkt 5:0 (cddr (cons 1 (cons 2 3))) -- pair
-TR opt: derived-pair.rkt 5:0 (cddr (cons 1 (cons 2 3))) -- pair
+TR opt: derived-pair.rkt 2:1 caar -- pair
+TR opt: derived-pair.rkt 2:1 caar -- pair
+TR opt: derived-pair.rkt 3:1 cadr -- pair
+TR opt: derived-pair.rkt 3:1 cadr -- pair
+TR opt: derived-pair.rkt 4:1 cdar -- pair
+TR opt: derived-pair.rkt 4:1 cdar -- pair
+TR opt: derived-pair.rkt 5:1 cddr -- pair
+TR opt: derived-pair.rkt 5:1 cddr -- pair
 END
 #<<END
 1
diff --git a/typed-racket-test/optimizer/tests/derived-pair2.rkt b/typed-racket-test/optimizer/tests/derived-pair2.rkt
index 0726f0b7..3b23b660 100644
--- a/typed-racket-test/optimizer/tests/derived-pair2.rkt
+++ b/typed-racket-test/optimizer/tests/derived-pair2.rkt
@@ -1,29 +1,29 @@
 #;#;
 #<<END
-TR opt: derived-pair2.rkt 2:0 (caaar (cons (cons (cons 1 2) 3) 4)) -- pair
-TR opt: derived-pair2.rkt 2:0 (caaar (cons (cons (cons 1 2) 3) 4)) -- pair
-TR opt: derived-pair2.rkt 2:0 (caaar (cons (cons (cons 1 2) 3) 4)) -- pair
-TR opt: derived-pair2.rkt 3:0 (caadr (cons 1 (cons (cons 2 3) 4))) -- pair
-TR opt: derived-pair2.rkt 3:0 (caadr (cons 1 (cons (cons 2 3) 4))) -- pair
-TR opt: derived-pair2.rkt 3:0 (caadr (cons 1 (cons (cons 2 3) 4))) -- pair
-TR opt: derived-pair2.rkt 4:0 (cadar (cons (cons 1 (cons 2 3)) 4)) -- pair
-TR opt: derived-pair2.rkt 4:0 (cadar (cons (cons 1 (cons 2 3)) 4)) -- pair
-TR opt: derived-pair2.rkt 4:0 (cadar (cons (cons 1 (cons 2 3)) 4)) -- pair
-TR opt: derived-pair2.rkt 5:0 (caddr (cons 1 (cons 2 (cons 3 4)))) -- pair
-TR opt: derived-pair2.rkt 5:0 (caddr (cons 1 (cons 2 (cons 3 4)))) -- pair
-TR opt: derived-pair2.rkt 5:0 (caddr (cons 1 (cons 2 (cons 3 4)))) -- pair
-TR opt: derived-pair2.rkt 6:0 (cdaar (cons (cons (cons 1 2) 3) 4)) -- pair
-TR opt: derived-pair2.rkt 6:0 (cdaar (cons (cons (cons 1 2) 3) 4)) -- pair
-TR opt: derived-pair2.rkt 6:0 (cdaar (cons (cons (cons 1 2) 3) 4)) -- pair
-TR opt: derived-pair2.rkt 7:0 (cdadr (cons 1 (cons (cons 2 3) 4))) -- pair
-TR opt: derived-pair2.rkt 7:0 (cdadr (cons 1 (cons (cons 2 3) 4))) -- pair
-TR opt: derived-pair2.rkt 7:0 (cdadr (cons 1 (cons (cons 2 3) 4))) -- pair
-TR opt: derived-pair2.rkt 8:0 (cddar (cons (cons 1 (cons 2 3)) 4)) -- pair
-TR opt: derived-pair2.rkt 8:0 (cddar (cons (cons 1 (cons 2 3)) 4)) -- pair
-TR opt: derived-pair2.rkt 8:0 (cddar (cons (cons 1 (cons 2 3)) 4)) -- pair
-TR opt: derived-pair2.rkt 9:0 (cdddr (cons 1 (cons 2 (cons 3 4)))) -- pair
-TR opt: derived-pair2.rkt 9:0 (cdddr (cons 1 (cons 2 (cons 3 4)))) -- pair
-TR opt: derived-pair2.rkt 9:0 (cdddr (cons 1 (cons 2 (cons 3 4)))) -- pair
+TR opt: derived-pair2.rkt 2:1 caaar -- pair
+TR opt: derived-pair2.rkt 2:1 caaar -- pair
+TR opt: derived-pair2.rkt 2:1 caaar -- pair
+TR opt: derived-pair2.rkt 3:1 caadr -- pair
+TR opt: derived-pair2.rkt 3:1 caadr -- pair
+TR opt: derived-pair2.rkt 3:1 caadr -- pair
+TR opt: derived-pair2.rkt 4:1 cadar -- pair
+TR opt: derived-pair2.rkt 4:1 cadar -- pair
+TR opt: derived-pair2.rkt 4:1 cadar -- pair
+TR opt: derived-pair2.rkt 5:1 caddr -- pair
+TR opt: derived-pair2.rkt 5:1 caddr -- pair
+TR opt: derived-pair2.rkt 5:1 caddr -- pair
+TR opt: derived-pair2.rkt 6:1 cdaar -- pair
+TR opt: derived-pair2.rkt 6:1 cdaar -- pair
+TR opt: derived-pair2.rkt 6:1 cdaar -- pair
+TR opt: derived-pair2.rkt 7:1 cdadr -- pair
+TR opt: derived-pair2.rkt 7:1 cdadr -- pair
+TR opt: derived-pair2.rkt 7:1 cdadr -- pair
+TR opt: derived-pair2.rkt 8:1 cddar -- pair
+TR opt: derived-pair2.rkt 8:1 cddar -- pair
+TR opt: derived-pair2.rkt 8:1 cddar -- pair
+TR opt: derived-pair2.rkt 9:1 cdddr -- pair
+TR opt: derived-pair2.rkt 9:1 cdddr -- pair
+TR opt: derived-pair2.rkt 9:1 cdddr -- pair
 END
 #<<END
 1
diff --git a/typed-racket-test/optimizer/tests/derived-pair3.rkt b/typed-racket-test/optimizer/tests/derived-pair3.rkt
index 98e6116a..3e47f0d5 100644
--- a/typed-racket-test/optimizer/tests/derived-pair3.rkt
+++ b/typed-racket-test/optimizer/tests/derived-pair3.rkt
@@ -1,69 +1,69 @@
 #;#;
 #<<END
-TR opt: derived-pair3.rkt 10:0 (cdaaar (cons (cons (cons (cons 1 2) 3) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 10:0 (cdaaar (cons (cons (cons (cons 1 2) 3) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 10:0 (cdaaar (cons (cons (cons (cons 1 2) 3) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 10:0 (cdaaar (cons (cons (cons (cons 1 2) 3) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 11:0 (cdaadr (cons 1 (cons (cons (cons 2 3) 4) 5))) -- pair
-TR opt: derived-pair3.rkt 11:0 (cdaadr (cons 1 (cons (cons (cons 2 3) 4) 5))) -- pair
-TR opt: derived-pair3.rkt 11:0 (cdaadr (cons 1 (cons (cons (cons 2 3) 4) 5))) -- pair
-TR opt: derived-pair3.rkt 11:0 (cdaadr (cons 1 (cons (cons (cons 2 3) 4) 5))) -- pair
-TR opt: derived-pair3.rkt 12:0 (cdadar (cons (cons 1 (cons (cons 2 3) 4)) 5)) -- pair
-TR opt: derived-pair3.rkt 12:0 (cdadar (cons (cons 1 (cons (cons 2 3) 4)) 5)) -- pair
-TR opt: derived-pair3.rkt 12:0 (cdadar (cons (cons 1 (cons (cons 2 3) 4)) 5)) -- pair
-TR opt: derived-pair3.rkt 12:0 (cdadar (cons (cons 1 (cons (cons 2 3) 4)) 5)) -- pair
-TR opt: derived-pair3.rkt 13:0 (cdaddr (cons 1 (cons 2 (cons (cons 3 4) 5)))) -- pair
-TR opt: derived-pair3.rkt 13:0 (cdaddr (cons 1 (cons 2 (cons (cons 3 4) 5)))) -- pair
-TR opt: derived-pair3.rkt 13:0 (cdaddr (cons 1 (cons 2 (cons (cons 3 4) 5)))) -- pair
-TR opt: derived-pair3.rkt 13:0 (cdaddr (cons 1 (cons 2 (cons (cons 3 4) 5)))) -- pair
-TR opt: derived-pair3.rkt 14:0 (cddaar (cons (cons (cons 1 (cons 2 3)) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 14:0 (cddaar (cons (cons (cons 1 (cons 2 3)) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 14:0 (cddaar (cons (cons (cons 1 (cons 2 3)) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 14:0 (cddaar (cons (cons (cons 1 (cons 2 3)) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 15:0 (cddadr (cons 1 (cons (cons 2 (cons 3 4)) 5))) -- pair
-TR opt: derived-pair3.rkt 15:0 (cddadr (cons 1 (cons (cons 2 (cons 3 4)) 5))) -- pair
-TR opt: derived-pair3.rkt 15:0 (cddadr (cons 1 (cons (cons 2 (cons 3 4)) 5))) -- pair
-TR opt: derived-pair3.rkt 15:0 (cddadr (cons 1 (cons (cons 2 (cons 3 4)) 5))) -- pair
-TR opt: derived-pair3.rkt 16:0 (cdddar (cons (cons 1 (cons 2 (cons 3 4))) 5)) -- pair
-TR opt: derived-pair3.rkt 16:0 (cdddar (cons (cons 1 (cons 2 (cons 3 4))) 5)) -- pair
-TR opt: derived-pair3.rkt 16:0 (cdddar (cons (cons 1 (cons 2 (cons 3 4))) 5)) -- pair
-TR opt: derived-pair3.rkt 16:0 (cdddar (cons (cons 1 (cons 2 (cons 3 4))) 5)) -- pair
-TR opt: derived-pair3.rkt 17:0 (cddddr (cons 1 (cons 2 (cons 3 (cons 4 5))))) -- pair
-TR opt: derived-pair3.rkt 17:0 (cddddr (cons 1 (cons 2 (cons 3 (cons 4 5))))) -- pair
-TR opt: derived-pair3.rkt 17:0 (cddddr (cons 1 (cons 2 (cons 3 (cons 4 5))))) -- pair
-TR opt: derived-pair3.rkt 17:0 (cddddr (cons 1 (cons 2 (cons 3 (cons 4 5))))) -- pair
-TR opt: derived-pair3.rkt 2:0 (caaaar (cons (cons (cons (cons 1 2) 3) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 2:0 (caaaar (cons (cons (cons (cons 1 2) 3) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 2:0 (caaaar (cons (cons (cons (cons 1 2) 3) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 2:0 (caaaar (cons (cons (cons (cons 1 2) 3) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 3:0 (caaadr (cons 1 (cons (cons (cons 2 3) 4) 5))) -- pair
-TR opt: derived-pair3.rkt 3:0 (caaadr (cons 1 (cons (cons (cons 2 3) 4) 5))) -- pair
-TR opt: derived-pair3.rkt 3:0 (caaadr (cons 1 (cons (cons (cons 2 3) 4) 5))) -- pair
-TR opt: derived-pair3.rkt 3:0 (caaadr (cons 1 (cons (cons (cons 2 3) 4) 5))) -- pair
-TR opt: derived-pair3.rkt 4:0 (caadar (cons (cons 1 (cons (cons 2 3) 4)) 5)) -- pair
-TR opt: derived-pair3.rkt 4:0 (caadar (cons (cons 1 (cons (cons 2 3) 4)) 5)) -- pair
-TR opt: derived-pair3.rkt 4:0 (caadar (cons (cons 1 (cons (cons 2 3) 4)) 5)) -- pair
-TR opt: derived-pair3.rkt 4:0 (caadar (cons (cons 1 (cons (cons 2 3) 4)) 5)) -- pair
-TR opt: derived-pair3.rkt 5:0 (caaddr (cons 1 (cons 2 (cons (cons 3 4) 5)))) -- pair
-TR opt: derived-pair3.rkt 5:0 (caaddr (cons 1 (cons 2 (cons (cons 3 4) 5)))) -- pair
-TR opt: derived-pair3.rkt 5:0 (caaddr (cons 1 (cons 2 (cons (cons 3 4) 5)))) -- pair
-TR opt: derived-pair3.rkt 5:0 (caaddr (cons 1 (cons 2 (cons (cons 3 4) 5)))) -- pair
-TR opt: derived-pair3.rkt 6:0 (cadaar (cons (cons (cons 1 (cons 2 3)) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 6:0 (cadaar (cons (cons (cons 1 (cons 2 3)) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 6:0 (cadaar (cons (cons (cons 1 (cons 2 3)) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 6:0 (cadaar (cons (cons (cons 1 (cons 2 3)) 4) 5)) -- pair
-TR opt: derived-pair3.rkt 7:0 (cadadr (cons 1 (cons (cons 2 (cons 3 4)) 5))) -- pair
-TR opt: derived-pair3.rkt 7:0 (cadadr (cons 1 (cons (cons 2 (cons 3 4)) 5))) -- pair
-TR opt: derived-pair3.rkt 7:0 (cadadr (cons 1 (cons (cons 2 (cons 3 4)) 5))) -- pair
-TR opt: derived-pair3.rkt 7:0 (cadadr (cons 1 (cons (cons 2 (cons 3 4)) 5))) -- pair
-TR opt: derived-pair3.rkt 8:0 (caddar (cons (cons 1 (cons 2 (cons 3 4))) 5)) -- pair
-TR opt: derived-pair3.rkt 8:0 (caddar (cons (cons 1 (cons 2 (cons 3 4))) 5)) -- pair
-TR opt: derived-pair3.rkt 8:0 (caddar (cons (cons 1 (cons 2 (cons 3 4))) 5)) -- pair
-TR opt: derived-pair3.rkt 8:0 (caddar (cons (cons 1 (cons 2 (cons 3 4))) 5)) -- pair
-TR opt: derived-pair3.rkt 9:0 (cadddr (cons 1 (cons 2 (cons 3 (cons 4 5))))) -- pair
-TR opt: derived-pair3.rkt 9:0 (cadddr (cons 1 (cons 2 (cons 3 (cons 4 5))))) -- pair
-TR opt: derived-pair3.rkt 9:0 (cadddr (cons 1 (cons 2 (cons 3 (cons 4 5))))) -- pair
-TR opt: derived-pair3.rkt 9:0 (cadddr (cons 1 (cons 2 (cons 3 (cons 4 5))))) -- pair
+TR opt: derived-pair3.rkt 10:1 cdaaar -- pair
+TR opt: derived-pair3.rkt 10:1 cdaaar -- pair
+TR opt: derived-pair3.rkt 10:1 cdaaar -- pair
+TR opt: derived-pair3.rkt 10:1 cdaaar -- pair
+TR opt: derived-pair3.rkt 11:1 cdaadr -- pair
+TR opt: derived-pair3.rkt 11:1 cdaadr -- pair
+TR opt: derived-pair3.rkt 11:1 cdaadr -- pair
+TR opt: derived-pair3.rkt 11:1 cdaadr -- pair
+TR opt: derived-pair3.rkt 12:1 cdadar -- pair
+TR opt: derived-pair3.rkt 12:1 cdadar -- pair
+TR opt: derived-pair3.rkt 12:1 cdadar -- pair
+TR opt: derived-pair3.rkt 12:1 cdadar -- pair
+TR opt: derived-pair3.rkt 13:1 cdaddr -- pair
+TR opt: derived-pair3.rkt 13:1 cdaddr -- pair
+TR opt: derived-pair3.rkt 13:1 cdaddr -- pair
+TR opt: derived-pair3.rkt 13:1 cdaddr -- pair
+TR opt: derived-pair3.rkt 14:1 cddaar -- pair
+TR opt: derived-pair3.rkt 14:1 cddaar -- pair
+TR opt: derived-pair3.rkt 14:1 cddaar -- pair
+TR opt: derived-pair3.rkt 14:1 cddaar -- pair
+TR opt: derived-pair3.rkt 15:1 cddadr -- pair
+TR opt: derived-pair3.rkt 15:1 cddadr -- pair
+TR opt: derived-pair3.rkt 15:1 cddadr -- pair
+TR opt: derived-pair3.rkt 15:1 cddadr -- pair
+TR opt: derived-pair3.rkt 16:1 cdddar -- pair
+TR opt: derived-pair3.rkt 16:1 cdddar -- pair
+TR opt: derived-pair3.rkt 16:1 cdddar -- pair
+TR opt: derived-pair3.rkt 16:1 cdddar -- pair
+TR opt: derived-pair3.rkt 17:1 cddddr -- pair
+TR opt: derived-pair3.rkt 17:1 cddddr -- pair
+TR opt: derived-pair3.rkt 17:1 cddddr -- pair
+TR opt: derived-pair3.rkt 17:1 cddddr -- pair
+TR opt: derived-pair3.rkt 2:1 caaaar -- pair
+TR opt: derived-pair3.rkt 2:1 caaaar -- pair
+TR opt: derived-pair3.rkt 2:1 caaaar -- pair
+TR opt: derived-pair3.rkt 2:1 caaaar -- pair
+TR opt: derived-pair3.rkt 3:1 caaadr -- pair
+TR opt: derived-pair3.rkt 3:1 caaadr -- pair
+TR opt: derived-pair3.rkt 3:1 caaadr -- pair
+TR opt: derived-pair3.rkt 3:1 caaadr -- pair
+TR opt: derived-pair3.rkt 4:1 caadar -- pair
+TR opt: derived-pair3.rkt 4:1 caadar -- pair
+TR opt: derived-pair3.rkt 4:1 caadar -- pair
+TR opt: derived-pair3.rkt 4:1 caadar -- pair
+TR opt: derived-pair3.rkt 5:1 caaddr -- pair
+TR opt: derived-pair3.rkt 5:1 caaddr -- pair
+TR opt: derived-pair3.rkt 5:1 caaddr -- pair
+TR opt: derived-pair3.rkt 5:1 caaddr -- pair
+TR opt: derived-pair3.rkt 6:1 cadaar -- pair
+TR opt: derived-pair3.rkt 6:1 cadaar -- pair
+TR opt: derived-pair3.rkt 6:1 cadaar -- pair
+TR opt: derived-pair3.rkt 6:1 cadaar -- pair
+TR opt: derived-pair3.rkt 7:1 cadadr -- pair
+TR opt: derived-pair3.rkt 7:1 cadadr -- pair
+TR opt: derived-pair3.rkt 7:1 cadadr -- pair
+TR opt: derived-pair3.rkt 7:1 cadadr -- pair
+TR opt: derived-pair3.rkt 8:1 caddar -- pair
+TR opt: derived-pair3.rkt 8:1 caddar -- pair
+TR opt: derived-pair3.rkt 8:1 caddar -- pair
+TR opt: derived-pair3.rkt 8:1 caddar -- pair
+TR opt: derived-pair3.rkt 9:1 cadddr -- pair
+TR opt: derived-pair3.rkt 9:1 cadddr -- pair
+TR opt: derived-pair3.rkt 9:1 cadddr -- pair
+TR opt: derived-pair3.rkt 9:1 cadddr -- pair
 END
 #<<END
 1
diff --git a/typed-racket-test/optimizer/tests/invalid-derived-pair.rkt b/typed-racket-test/optimizer/tests/invalid-derived-pair.rkt
index 188fcb08..547d1b94 100644
--- a/typed-racket-test/optimizer/tests/invalid-derived-pair.rkt
+++ b/typed-racket-test/optimizer/tests/invalid-derived-pair.rkt
@@ -1,7 +1,9 @@
 #;#;
 #<<END
-TR missed opt: invalid-derived-pair.rkt 10:6 (cadr x) -- car/cdr on a potentially empty list -- caused by: 10:6 (cadr x)
-TR missed opt: invalid-derived-pair.rkt 5:2 (cadr x) -- car/cdr on a potentially empty list -- caused by: 5:2 (cadr x)
+TR missed opt: invalid-derived-pair.rkt 10:7 cadr -- car/cdr on a potentially empty list -- caused by: 10:12 x
+TR missed opt: invalid-derived-pair.rkt 5:3 cadr -- car/cdr on a potentially empty list -- caused by: 5:8 x
+TR missed opt: invalid-derived-pair.rkt 5:3 cadr -- car/cdr on a potentially empty list -- caused by: 5:8 x
+TR opt: invalid-derived-pair.rkt 10:7 cadr -- pair
 END
 ""
 #lang typed/racket #:optimize
diff --git a/typed-racket-test/optimizer/tests/list.rkt b/typed-racket-test/optimizer/tests/list.rkt
index e54ddb1e..89134724 100644
--- a/typed-racket-test/optimizer/tests/list.rkt
+++ b/typed-racket-test/optimizer/tests/list.rkt
@@ -1,18 +1,17 @@
 #;#;
 #<<END
-TR opt: list.rkt 3:0 (first l) -- pair
-TR opt: list.rkt 4:0 (rest l) -- pair
-TR opt: list.rkt 5:0 (second l) -- pair
-TR opt: list.rkt 5:0 (second l) -- pair
-TR opt: list.rkt 6:0 (rest (rest l)) -- pair
-TR opt: list.rkt 6:6 (rest l) -- pair
-TR opt: list.rkt 7:0 (third l) -- pair
-TR opt: list.rkt 7:0 (third l) -- pair
-TR opt: list.rkt 7:0 (third l) -- pair
-TR opt: list.rkt 8:0 (fourth l) -- pair
-TR opt: list.rkt 8:0 (fourth l) -- pair
-TR opt: list.rkt 8:0 (fourth l) -- pair
-TR opt: list.rkt 8:0 (fourth l) -- pair
+TR opt: list.rkt 3:1 first -- pair
+TR opt: list.rkt 4:1 rest -- pair
+TR opt: list.rkt 5:1 second -- pair
+TR opt: list.rkt 5:1 second -- pair
+TR opt: list.rkt 6:1 rest -- pair
+TR opt: list.rkt 7:1 third -- pair
+TR opt: list.rkt 7:1 third -- pair
+TR opt: list.rkt 7:1 third -- pair
+TR opt: list.rkt 8:1 fourth -- pair
+TR opt: list.rkt 8:1 fourth -- pair
+TR opt: list.rkt 8:1 fourth -- pair
+TR opt: list.rkt 8:1 fourth -- pair
 END
 #<<END
 1