This is probably a dumb question, but do full scale aircraft use off set thrust to counteract engine torque? If not, why not? If they don't, then why do our models require it to fly properly? Just wondering....................Jerry

Yes, they do.

If you get around a T-28 sometime, this big beast has what looks to be about 6 degrees of downthrust. Side-thrust is harder to eyeball.

Models are "real" planes, and all the rules apply.