What we do is to make our changes and after experience says if
we are using them or not, we keep them or delete them. I just deleted
the Ignore command I added time ago to acme because we found that we
have seldom used it.

Regarding 3-1, paurea is using it a lot on directories, I've used it
several times these days, but I still don't know if that's really useful
for me or not. If after some time we find that we seldom use it, we'll
delete that feature; but I think that we'll be using it a lot (at least
paurea is doing so, and I think I'm going the same way).

On files, I *never* used 3-1. Well, I used it once when I first tried
acme, just to play with undoing buttons. I don't know for sure, but I
think paurea never used it either.

Most times, I notice that I used 3 to open a wrong file (eg /dev/zero and
alike) after I released the button (which makes 3-1 no longer useful as
a cancel).

On the other hand, we had 2 on directories instead of 3-1 some time ago.
It was confusing because some directories correspond to program names in
/bin. That's why we decided to move to 3-1 instead of keep on using 2.