Sometimes, if you do a 2-URL merge from a foreign repository (that is, a
repository that differs from the repository represented by the merge target
working copy), the result is that the target working copy is left with DAV
wc-props that represent version source URLs pointing to the foreign repository.
In other words, while the primary working copy administrative data indicates
that all is well, some underlying DAV-layer cache gunk claims that files which
should live in the repository from which the target working copy comes instead
live in the (different) repository from which the merge was performed. That's bad.
(I'll be posting a recipe script soon.)