Kolsch, overpitching ok?

I don't have the space to set up a fermentation control cabinet, so I've been relying on swamp cooling to ferment cooler kolsch's in the summer.

Could I pitch on a yeast cake to overpitch to make a cleaner beer to compensate for lack of ferm temp control?

There's a very long thread on this topic somewhere on the forums that is by turns informative and angry. It's a worthwhile read, but the Readers Digest Condensed Version is that pitching onto an entire cake gets you a beer so clean it's boring. Kolsch is so clean already that I would pitch at normal levels and swamp cool the heck out of it. If you have a cooler large enough to fit your bucket in, you have the makings of an excellent swamp, even if you can only submerge it halfway.