Not really: its clearly documented: only an issue marked blocker can delay a release candidate build: http://wiki.apache.org/lucene-java/ReleaseTodo
This is not a rule. Nor an excuse to just flip back something someone changed with 0 discussion.
I think its totally natural to expect me to try to push back on last minute stuff getting shoved into the release
So push back - don't revert someones change 2 seconds after they made it.
especially if these were not INTRODUCED in 3.1, don't have any patches at all, only refer to a misconfigured case where someone didn't index their content correctly, and could be fixed in 3.2 instead.
LUCENE-2939 was marked 3.1 last night. This is that issue if you cannot tell. They should both be marked the same in either case.