unison -times
After more than one year using unison to synchronize most of $HOME
between my laptop and desktop, I discovered yesterday that unison can
propagate file modification time, which does not by default. Just pass
-times (or set times = true in the configuration file).
The first sync with -times results in a huge conflicts with “revprops”
being changed in both sides. I resolved all of them in favour of the
less recent file (there’s a menu option for that in unison-gtk). But boy
did it take long to sync all files.