I'm opposed to the notion of procedurally fiddling with carb heat at 200' feet up on final. This is the phase of flight when minimizing "things to do" in the cockpit is good. Rather that pre configuring the aircraft for a slight chance go around, why not leave it configured as described in the POH, and only reselect carb heat on that very infrequent occasion when a go around might be required, you'll have time... The plane will go around with carb heat hot if it has to, and once you have your focus on flying the overshoot, then you can come back to the engine controls!
Exactly, why make things more complex than is necessary.