I think that if its not allowed in Tournament play then you obviously cant use it. But if you are gambling why not be allowed to use it? It isnt very often that you would need one it just makes for an extra weapon in the arsenal. And for the guy who said jumping is a poke and hope? HMMM, he must not know how to jump, because when I jump its almost always gauranteed....you have to know your limits obviously.
My full time playing cue, is a Rick Howard jump break cue, it plays very very well, I never break it down to jump though, only use it to break and play with I have a seperate short jump cue that I used to hate until I learned HOW to use it, NOW it has gotten me out of many situations,
I also know HOW to kick at balls one, two and three rails, using the diamonds but sometimes it is just as safe if not easier to jump at a ball than kick at it......
Just my Opinion, I think the biggest thing that should be RULED OUT in pool nowdays is the BALL IN HAND RULE. It makes it to easy for a retard to get out. BALL IN HAND behind the head string would be better more skill and strategy involved in that one, of course I am talking about nine ball and eight ball, because one pocket is already behind the line, can you imagine what would happen if you got ball in hand anywhere on the table in one pocket