Jeff King [off-list ref] writes:
Sorry, I mean the case where you do a merge from the other side, but
then you end up rewinding the history in some way, taking into account
that merge and everything they did. For example:
$ git pull
$ git rebase ;# this will flatten the merge
$ git push --force-with-lease
There was never a moment where the other side's tip ref was in your
local branch, but you did incorporate it via the merge.
Ah, OK, now it is clear what you meant.
Thanks.