Centaurus, I was staying in a town on business and spontaneously went for a bash in a C152 late one summer evening. As I was unfamiliar with the area I went with an instructor who showed me the sights. It was an awesome flight over the coast and I asked if we could return to the field for a few touch and goes.
On turning base I completed the checklist from memory and verified against the written one in the aircraft (as is my habit). Naturally before pulling the throttle back I applied full carb heat.
On very short final I went to push the carb heat to COLD. The instructor balked at this and immediately pulled it back out to ON. I didn't say anything and touched down, retracted the flaps, then went to push the carb heat back to cold again before applying full throttle. He practically smacked my hand away and said "leave it on". He left the carb heat on until approx 300ft AGL and then he set it to COLD.
I was confused by all of this. His explanation was that it was their standard operating procedure and that it reduced the likelihood of carb ice accumulation during the critical take-off phase. Clearly there was no arguing with him so we finished up the next circuit with a full stop.
Who was right or wrong in this situation? The C152 POH says that any normal takeoff should be with carb heat COLD, and as part of the BEFORE LANDING checklist it should be set ON. It doesn't make mention of if it should be set to COLD on short final!