> Try this:
>
>         self do: [:i | ] separatedBy: []

Ha, ok, well, score +1 again for formatting code with more spacing in
it (total score:  3-1).  ;-)  I never noticed "block args" having the
problem since I always use more spacing (and, I guess, the code in the
system I've ever traced).

So the real issue appears to be related to when a colon follows a
non-whitespace character, as it does in your example and in
keyword-selector symbol case:

      self perform: #add: with: anObject

I just saw Bobs msg did half the work finding the method..  Hmm..