The only T67 I've flown was a T67A with a small engine, fixed pitch prop and forward fuel tank. We had to weigh both pilots, then add fuel very carefully to make sure that the CofG was within limits for spinning and aeros.
It was an excellent device for teaching correct stall recovery technique, very good for teaching incipient spin recovery and also for demonstrating fully developed spins. But b****y awful for teaching aerobatics as you had to spend most of the time preventing the engine from over-revving.
Quite fun if one's student got slow at the top of a loop though - it would either slowly flick erect or if very slow the engine would stop. Literally - the prop always looked huge when it stopped in front of you. A quick push on the starter button invariably got it going again though. But I always stayed within gliding range of somewhere friendly when aerobatting, just in case.....
Stalling in the turn was good - just invite the student to fly a 45 deg banked turn, then move the control column back a couple of inches...... 'Undemanded roll' sure as eggs!
It was a playful little thing, but what an utterly dismal roll rate compared to the Bulldog or Chipmunk! Unless you cheated and flicked it, that is.