We've all done it, slip the clutch too much during a hard launch. Happened to me yesterday, and there was a funky smell. My question is, to cool down the clutch and prolong it's life, should you disengage the clutch for a while to dissipate heat as quickly as possible? Or does it not matter?
The clutches pressure plate will dissipate heat on its own just fine via the flywheel and cover. The plate is made to slip and endure heat cycles, however standard type clutches are NOT designed for 'heavy' launches over and over. After a while the springs will start to weaken and the friction material will suffer from heat damage. The clutch material can then become brittle and begin to degrade & crack apart due to excess heat. I've even seen clutches that have been so hot the cover and flywheel surfaces have turned a nice blue colour from the heating process. And just like brake pads they can become hard & glazed which is not good.
It doesn't matter. The clutch doesn't slip anymore as soon as you either let go of it completely or push it in all the way. In theory there's no friction at those moments, and no friction means no heat added. It only creates heat when it slips. Just temper your enthusiasm a bit if you start to smell the characteristic brakepad/clutch fumes. I very much doubt that heat dissipation goes any faster when you declutch. It depends on the temperature of the flywheel, which i don't suppose will ever get hotter than the clutch because of the much larger thermal mass it has.