That's strange. I've been able to edit and delete my comments in restricted subs too, even with a banned account.
As long as the subs are just restricted you are able to edit and delete your posts (at least manually, I didn't try that with a programm). But when a sub is private you don't have access to your posts.
That's strange. I've been able to edit and delete my comments in restricted subs too, even with a banned account.