Sorry to bump this, but...
Yes, the new automerge feature is strange.
Before it was 10/15 minute wait in order to avoid posts merged.
But now, even if two posts are months old, as long as last and new post is made by the sane user, it will automerge with the "last edited by USER just now" legend when it happens.
I get its annoying to post continually, but this automerge just killed some threads with constant posts. I'm talking about the "post here funny pictures" thread. I mean, the thread was active by the same 5/6 members that continually posts pictures.
Now it's not.
Can't we go back to old waiting 10/15 minutes in-between same user post in order to prevent automerge system?