I'll give this a shot.
The more your wrist is cupped the more lift/rev's you'll get. I'll try to diagram this a little.
Hand position from your ball hand side.
\ More revs/lift.
| Less revs/less lift
/ Minimal revs/ minimal lift.
Now those are what I call the wrist adjustments.
Here is what I had explained to me about the hand adjustments.
Viewed from the palm of the hand for a right hander.
| Hand is in-lined with the wrist/forearm. Will provide more revs/lift. Which would cause the ball to skid farther before getting its roll.
/ Hand is cocked or off-set from the forearm will cause the hand to stay behind the ball more, causing less lift and an earlier roll.
I would say that most people like to get an earlier roll on wet lanes to get more hook out of the ball. Then they would want more revs on dryer lanes to skid through the heads and delay the big hook until down the lane.
I personally found a hand/wrist position I felt comfortable with and do all my adjustment with feet and mark position changes. This way my release is consistent. Except for shooting spares at the 6,9,or 10 pin, then I adjust my wrist position so it's less cupped so I get less lift and stay behind the ball more for a straighter shot. If you use a spare ball I wouldn't change my hand positions.
There are always some exceptions though. Sometimes depending on the lane conditions you may have to change hand position.
There are only 10 types of people in this world. Those who understand binary and those who don't.