diff -r b6713e04889e -r a8babbb6d5ea src/Pure/goal.ML
--- a/src/Pure/goal.ML	Mon Jul 13 19:25:58 2015 +0200
+++ b/src/Pure/goal.ML	Tue Jul 14 11:29:43 2015 +0200
@@ -230,7 +230,9 @@
             result)
           (Thm.term_of stmt);
   in
-    Conjunction.elim_balanced (length props) res
+    res
+    |> length props > 1 ? Thm.norm_proof
+    |> Conjunction.elim_balanced (length props)
     |> map (Assumption.export false ctxt' ctxt)
     |> Variable.export ctxt' ctxt
     |> map Drule.zero_var_indexes