That may be in some respects, but I've seen a lot of so-called 9-ball mechanics not fare so well when playing one-pocket. It's not only the strategy of the game which needs to be learned, but it's also the touch, the feel shots. You gotta know when to go for 'em, know when to play safe, et cetera.
9-ball player shooters are more offensive than defensive, at least the ones I've seen, as a general rule. Whereas, one-pocket players are more defensive than offensive. You don't see very many one-pocket players run a rack like you do in 9-ball.
There's a plethora of pocket billiard games, each with different strategies and skill sets: banks (long rail, short rail), rotation (3-ball, 6-ball, 7-ball, 8-ball, 9-ball, 10-ball, 15-ball), one-pocket, 14.1 (straight pool), et cetera.
And then there's snooker, which is a whole nother topic altogether. It's kind of comical watching a 9-ball mechanic try to shoot a ball down the rail on a snooker table.
We used to play 9-ball on snooker tables many moons ago, and, man, that's one tough ring game. In order to succeed, one must be proficient in all games and have a lot of shots in their arsenal. One-trick ponies will not survive in that ring game. :embarrassed2: