I also favour the automatic selection of Carb Heat on the base leg as a precaution - but we also select it back to cold approaching 200' so that we are prepared for the go-around which is initiated if, at 200', the runway isn't clear, you are not happy with the approach, or landing clearance hasn't been given.
Just to go one stage further - I would like to enquire about the use of Carb Heat in the climb (apart from on the go-around where I agree you need all the power you can get). I teach, as I am sure most people do, that carb heat should not be selected hot when at full power as there is a detonation risk. However our Head of Training has recently suggested that this is a misconception and that because the Pilot Operating Handbook doesn't warn against this it doesn't necessarily apply. Anyone care to clear this up for me.
Cheers
PJ
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Your village called, their idiot is missing