Negative Charlie
Just because an instructor says something doesn't mean it is necessarily good airmanship.
An instructor in the US once asked me to change tanks when we were positioning for departure on the runway following a full stop during a circuit detail. We could have stopped at the run up area, but this guy didn't see the need for another power check.
I gave him some pretty polite but firm feedback about that.
If an instructor asked me not to shout clear prop, we would be having a discussion about why (becuase I don't have the monopoly on knowledge and there might be a good reason), but if I wasn't satisfied I be thinking quite seriously whether I wanted to fly with the guy/gal.