I think with regards to this it depends what climate you are flying in. If flying in the UK there is a big chance for carb. icing.
I was very surprised first time I flew here in the UK, as we I did not use Carb. heat as much when I was in Scandinavia flying.
But I believe my instructors words here in the UK are quite logical, it is better to have 80 - 90 % power for a go around, then nothing!
I have been thought here, Carb Heat checked on for Downwind, then off, after turning base and Carb Heat on until landing, Carb Heat on during all descent/ low power settings.
In the case of a go around, how long time will it take to move your hand from throttle to the carb heat switch?
And the RPM drop with Carb Heat on, is very little - specially with the climate in the UK, the go around might end with engine failure an forced landing - I personally would rather prefer to have 10 % less power when starting go around procedure.
Of course if you are flying in a dry hot/cold climate - you don't need to use this procedure.