[redan]

Chapter 4 of Hebron's Secrets and Lies book goes into this in great detail. Bob Bush, former Titleist designer responds to a Q&A from Hebron.

It feels like you're hitting "up" but that's because of how the weight is distributed in the clubface. Mike Tait of SMT says the sweet spot is a smidge up and in from the center of the club. No one has remembered in this thread that the ball moves while on the club face, inside quadrant and all that good stuff, so sweet spot being up and in makes sense to me...Watch Yoda's video with Brian G for good practical driver technique.