The fact that he's saying people will talk on aim suggests that his idea of a group is a bunch of people who know who each other are, ooc.

That stinks, even before you start considering "designer" groups.

I'd say stick with the puzzles, and if you find that a whole ooc group (e.g. russians, Dio VIPS, brits, aussies whatever) is using homogenous methods in the tower, ban them. That's almost certainly a sure sign of selective information sharing on an ooc basis, even if it is dressed up as being ic.