Just from my very limited personal experience I'd have to side w/ Kal. I kinda tried it for a while (though not quite at 200W per connection) and the biggest difference I noticed was probably due to my expectation that there would be a difference. Then I got the chance to hook up another amp (straight 2-ch, no bi-amp) and can honestly say that we all heard a significant and positive difference from "just" those two quality channels. It's not very precise nor measurable term, but the 100s just came alive. The other amp was an Odyssey, and for the first time I decided that there actually could be an occasional something to all the discussion of synergy.
It's not that bi-amping, done properly, is a bad idea (see Elliot Sound Products, etc. for a good description). It just seems that getting enough power w/ the qualities provided by that 2-ch was a more straightforward and satisfying solution for the 100s, at least to this boy.