Hmm, yeah :-(

I was hoping that reducing it would help us to trace the error (what is the
minimal set of patches we need to manipulate in order to generate this mystery
hunk), but I guess it didn't really help.  I tried looking through the
bug-{desktop,laptop} for a hint, but no luck yet.

One possible tip: notice that the email addresses attached to the patches are
different.  It seems like the 'Gour <dev@atmarama.org>' address is for the
desktop and the 'dev@atmarama.org' is for the laptop.  Maybe this can help us
reconstruct the events that led up to this bad conflictor.

Is there any hope for darcs repair to fix something like this?  

In general, it might be nice for recovery, if there was something like a darcs
rebase that let us yank out a patch and put something else in its place, if you
know what I mean. [maybe I just got the idea of rebase wrong, but sort of a
super-duper unsafe amend-record that lets us change patches and shift
dependencies accordingly]