A wrist roll does not have to go down after it is done as you demonstrate. A swing with wrist roll can be correctly on plane. Do not blame not staying on plane with rolling the wrists. However, too early with the wrist roll simply makes it a bit harder to strike the ball where you want it to because there is a slight upward movement (typically) in the middle of the roll. Try yourself in slow motion to see.
Thanks for the comment and discussion. I didn't think I said anything about staying on plane, so I went back and listened to the video again to make sure. Also, it was just a brief point on the differences between the two. I would also add that a wrist 'snap' the result of an action earlier in the swing; lag. I would agree that some players in some AB's could stay on plane as they roll the wrists, but as the wrists begin to roll the barrel begins to travel above the hands and plane of the pitch bringing the barrel more in contact with the top of the ball-ground ball. Not that all ground balls are bad, but in higher ball ground balls convert to outs more often. I am sure there have been hitters in history that have had success, but they are typically the exception to the rule as in many things in hitting or pitching, or sport in general. The real problem for me is when does an early frost roll occur and why? I think we have figured that out for the majority of hitters. Also, every hitter is an individual and one solution does fit all, hence the use of solving issues. As an instructor trying to help hitters solving problems/issues to help the hitter build a more fundamentally sound and repeatable swing is the goal.
