Just looking at the documentation is enough to make me wary: all of the default conflict resolution strategies[1] will, by design, throw away data in the event of a conflict (except for "skip" and "abort", which probably don't do what you want either).
Supposedly you can write a custom conflict handler (in Perl, naturally). But I find it worrying that a feature that's so critical for correctness is also entirely undocumented. I found an open issue to write some docs[2], which refers the curious to a single unit test that was deleted in 2011 with the commit message "Spelling cleanups, other maintenance" [3]. Doesn't inspire a lot of confidence.
