Pulling a vacuum on the crankcase will aid in ring sealing, but you are not going to see it with the KLEEN valve on the 10. It just does not pull enough of a vacuum to be able to do this.
Most race teams that do this, ie nascar, indy, and maybe the drag racers are using a dedicated vacuum pump plumbed thru the pcv syystem. I ahve yet to see a true vacuum system on any of the major bikes in any form of racing to do this yet.
I would much rather get rid of the extra crap and make the engine bay cleaner than deal with the crap from the KLEEN valve. Someone had a dyno graph with before and after runs with this mod and it does absolutely nothing for power on the 10.