Further to MattyJ,
Do any of that in a GTSO and you've just killed that engine.
You mean a GTSIO? I'm not aware of any GTSO's.
I don't see how it would kill it. Provided you chopped the throttle quickly without a slow retard to prevent gear 'chatter' then it would be the same as any other engine. obviously repeated assaults wouldn't be kind to the engine and I don't know to many operators that are happy for training to be conducted in their C404s.