You might start with the fingers under the ball, but then come over the top with them...
I could have said this better - You might start with a firm wrist, and the hand behind the ball. Then as you rotate around the ball, your wrist goes limp, placing the fingers on top of the ball instead of to the side of the ball.
This is why I recommended working out with kettlebells - to make your wrist strong enough to not "drop" the ball as you're releasing it.
Another point - in the releases I do, the midroll is applied by rotation of the wrist around the ball. The side roll is applied by the dropping of the ball off of the hand. If the hand is held in a steady position, and the ball allowed to drop off it, then side revs are applied at whatever angle the wrist has to the lane, regardless of the path of the pendulum swing. The ball will follow the path of the pendulum swing down the lane, with rotation to the side.
If the wrist goes limp as the ball is dropping off it then the revs of the side roll are reduced. The danger of rotating around the ball is that you might pull it to the left. This can happen when you hang onto the ball instead of letting it drop off.
"If it ain't workin', you're either throwing the ball wrong or throwing the wrong ball."
"Follow the oil!"
"Dry lanes ain't worth a shot!"
"I love the smell of lane conditioner in the morning!"
current avatar is Gabby Hayes. Looks a lot like me!