In the drill where you set up two object balls on the end rail, with a certain amount of space between them at least as large as another ball, and try to hit the rail between them from the other end of the table. I was just wondering what a reasonable expectation for the amount of space needed to do this successfully. (Not you semi-pro guys who never miss a shot, but say for a C player and up.) For me, it was harder than I thought. It's a wonder I can ever sink a shot that's more than a few feet away.