I'm working with a great instructor (Brian Manzella -brianmanzella.com) and this is the reason you don't want a high finish. When you finish high, the clubface is more open at impact (pre-impact to separation). Many times, this is due to a person trying to add height to their shot.

What he has me do is swinging left (after impact) with secondary axis tilt...and finishing with the club going more left and across the top of the chest...finishing lower.

If you do this and add the secondary axis tilt, you'll get a nice straight shot or slight draw. if you don't add SAT, you will hook it because the club will be closed.

Hope this makes sense and helps.