I find that my Duke runs very cool. I never feel heat pouring off of it even in the hottest weather and when I feel the motor after turning it off, I am amazed at the not too hot temperature of it.
I don't see the need either. Can't say about racetrack use, but I rode my Duke pretty hard this very hot summer and it stayed in the middle of the heat range on the gauge. Yesterday I really beat it ie. extended use at 6k to 8k rpms and the gauge stayed centered. It was cool out but still impressive.
BTW, when I got stuck in heavy stop and go traffic the fan always worked to keep the bike cool.
THinking about it, I wonder if it actually would do any good. I suppose if oil pumps must move the oil through the cooler, the oil pressure getting to the critical points must be lower than originally.
Does any of you know haw the piping set-up is made for this part?