It seems that Eric applied an older version of the patch below to the
main repo, which meant that I pulled it back in.  Apparently the only
thing I had changed in my local, amended copy was the timestamp.

I wouldn't even have noticed that there was a duplicate patch in my
repo, except that I was pulling a patch with "Trent" as the author.
Perhaps darcs should warn when a "duplicate" non-conflict is applied?

$ darcs obl --match 'date "2008-12-26T21:42:43+1100"'
Fri Dec 26 21:42:43 EST 2008  Trent W. Buck <trentbuck@gmail.com>
  * Improve readability of bug reporting.
  Moving "at <location>" to the first line gives the descriptive string
  a line all to itself.  For example, darcs show bug:

      darcs: bug at src/Darcs/Commands/ShowBug.lhs:57 compiled Nov  4 2008 12:05:43
      This is actually a fake bug in darcs.
Shall I obliterate this patch? (1/1)  [ynWsfvpxdaqjk], or ? for help: v
[...] duplicate
|hunk ./src/Darcs/Bug.hs 19
|-    errorDoc $ text ("bug at "++_bugLoc bs) $$ s $$
|+    errorDoc $ text "bug in darcs!" $$ s <+> text ("at "++_bugLoc bs) $$
|:
hunk ./src/Darcs/Bug.hs 19
-    errorDoc $ text "bug in darcs!" $$ s <+> text ("at "++_bugLoc bs) $$
+    errorDoc $ text ("bug at "++_bugLoc bs) $$ s $$
Shall I obliterate this patch? (1/1)  [ynWsfvpxdaqjk], or ? for help: y
Finished obliterating.

Thanks Trent. I am not sure this is the right thing, but based on your designating 
this a "wish" in the title, I prioritize and defer accordingly.

Best regards
Thorkil

Deferring was a mistake, sorry. Setting the need-info state instead, asking for a 
discussion of whether we should work to support this suggestion.

Best regards
Thorkil

I think issuing a warning for every duplicate that darcs generates is a
very good idea.