Jeff King [off-list ref] writes:
I can think of two other user-visible changes which have been discussed
that might warrant such a version bump:
- option parsing tweaks (hopefully these should be minor, but it is
clear that we cannot be 100% consistent while retaining the
identical previous behavior)
This could have a fallout, like *-default disambiguation which scripts
did not have to implement.
- moving dashed forms out of paths
This is already planned for 1.5.5 and it is not among "other
user-visible changes". Technically the use of git-foo form without
preparing the environment has not been supported for quite some time,
but people have come to rely on it and I'd agree this warrants a 1.6.0.