Might be a bit expensive, but I can see the sense in an electrical clutch ( like on the S/C ) being on both the alternator and the water pump. ( I think I'd want to keep the P/S pump )
Say have them de-energized at > 4000 RPM, think of the power savings, and I don't believe it would be a problem in a drag race scenario, road racing maybe.
Anyone thought of this ?