I doubt that the use-case that is tested here makes sense.
To me, the obvious workflow to resolve notes conflicts is is chdir into
this directory, edit files, and then call git notes merge --commit. The
(implicit) requirement that one cannot call commit from within the
directory you edited files was quite surprising to me. So in my opinion
the use case does make sense, which is why I submitted the bug in the
first place.
In any case, it should not fail silently, whether or not one is required
to chdir back to the worktree before calling git notes merge --commit.
d