I'd guess a slightly smaller percentage. I think the problems arise as usual in the gray areas.Bob,
I don't think it is any harder than, say, ball first rail first determinations in 3-cushion. I would say that 99 percent of the time it is obvious.
Mark
Sometimes when shooting a draw shot I get only part of the draw I expect and when I look at the tip I notice that there is not a full-blooded miscue with a bare brown spot on the shoulder of the tip but instead there is a whitish patch. Assuming I'm the kind of sport who would call a foul on himself, should I pipe up under the new rule? Suppose I notice my opponent similarly puzzled by one of his own failed draw attempts. Should I ask to inspect his tip?