Firstly, if the approach speed is way too high, the rate of decay even at idle power will mean that the average pilot won't be able to control the aircraft with sufficient finesse during the flare. The aircraft will float and wander in an uncontrolled manner.
Ignore airliner-driver rubbish about increasing approach speed in light aircraft in gusty conditions, Lister, to my mind it's clear that you're flying the aircraft in a sound, safe manner and that your old CFI's experience and wisdom was 100% correct.