Doubt this will get posted as I seem be banned from posting now, but what the hell.....
For miss the ding putters having the grid dots moving on the down swing is important as there is a difference between the preview grid speed and the shot speed.
If you miss the ding for the preview speed you will be under the cup most of the time as the break is actually harder than it appears in that view. If you putt for the downswing break it is usually much closer.
I actually wonder if that's the real reason they shut it off, so you're always looking at the wrong break speed.