That shot does come up often,,I agree. It came get you out of a tough spot ,but the table/rails that your on,, has allot to do with it. How active the rail is ,,,makes a huge difference.
I just tried it on my table,,not the first time ,but the rails on my Valley 7 1/2 footer are so active it is very easy to get over the ball. Actually have to hit it light or the cue will hit your in the head. Its not a good table to practice this shot on because most other tables ,,I know have to be hit rather firm to get the cue up and over.
I just jumped the cue over the first ball,,like planned,,, and missed the ball intended to go in,,,missed by Millimeters and got air off the second rail ,,clearing OB. lol
I do like this shot. Its really not that hard ,,if you know what reaction your going to get from the rail.
I will be practicing this anyhow,,,you put it in my mind . I am going to master it.