Don't assume .WHAT and friends are normal

Some of them may be implemented as normal methods or operators for now,
but we still reserve the right to change any of them into magical ponies.

S12-objects.pod

@@ -13,8 +13,8 @@ Synopsis 12: Objects
 
     Created: 27 Oct 2004
 
-    Last Modified: 30 Dec 2013
-    Version: 133
+    Last Modified: 26 Oct 2014
+    Version: 134
 
 =head1 Overview
 
@@ -2300,9 +2300,18 @@ These may be used either as methods or as unary operators:
     $obj.WHAT   # method form of P5's ref
     WHAT $obj   # unary form of P5's ref
 
-These are all actually macros, not true operators or methods.  If you get
-a foreign object from another language and need to call its C<.WHERE> method,
-you can say:
+These should all be considered built-in language primitives, not
+true operators or methods, even if a given implementation happens to
+implement one or more of them that way.  The optimizer reserves the
+right to assume it knows what these names mean without user meddling.
+Do not attempt to override or overload them, or bend them into twisty
+little brain pretzels, except to fulfill those parts of the standard
+interface that require you to do so.  (Value types, for instance,
+currently require a definition of WHICH.  This too may change as
+our notions of identity are refined.)
+
+If you get a foreign object from another language and need to call
+its C<.WHERE> method, you can say:
 
     $obj."WHERE"()