Collapsing the tree's easy, I did it for a client a few months ago. I didn't integrate it into our OpenACS 3 tree for two reasons, one of them still valid, i.e. it was part of a large rewrite which unfortunately for the most part wasn't of general interest (tied deeply into their own specific needs) and I thought we could just do it for OpenACS 4 which would be out by, oh, six months ago or whatever.
In other words, it was back before I knew that the original ACS 4 release would be something of a fiasco and therefore back when I thought we'd shift our efforts entirely to OpenACS 4 long before it's going to happen.
I suggest you submit it as an SDM feature request for the OpenACS 4 version. It's easy to implement and there's no reason not to have it available for our first release.
