Moon High Drives!

[Zeph]

And you should be hitting up on the ball with the driver.

Re-Examining Advice: Hitting Up with the Driver

Yet the majority of PGA Tour golfers hit the golf ball with their drivers coming into the ball flat or on a slight (typically 1-3 but 4 to 5 degrees maximum) downward angle. Very few hit up on it as much as the magazine article wanted you to do (five degrees IIRC). [...] The thought of hitting up on the driver can cause all sorts of problems. It can cause your upper body (your left shoulder) to fall back throughout the downswing. It can cause you to flip at the ball. It can cause other problems too.

[burnabao]

It's probably a fair compromise to agree that although hitting "up" on the ball might be a bit of an exaggeration, the feeling should be "more up" (or perhaps "less down"?) than compared to an iron-shot off the deck.

[Zeph]

Yes, but we are talking about a 2-4 degree difference, hard to measure when swinging. The longer shaft, wider arc and flatter plane will make the swing more shallow.
Maybe saying "hit down" can cause some to hit it like a wedge, that's not the point. Just want to get away from the thought about hitting the ball on the way up. It can lead to flipping, reverse pivot et cetera.

[alexhwang]

If you can check out your swing in a high speed camera it will help you a lot. If you lose your lag way too early you can bet part of it is your swing.