I knew one guy that did (Mike ???- can't remember the last name). Bet a guy in the bar using the broom stick in the back. Unscrewed it and scuffed the end. Used center english and beat the guy to death.
Benny Z. plays at my local place. He will use my Jacoby heavy hitter break/jump and run out on the hardest table in the place. He actually plays quite well with it,lol. And it has a phenolic tip...
I bet he had a cooperative broomstick, one which could at least make stop shots! But you cant tell me the same guy doesn't play way better with a decent cue.
Now on a 9 footer, no way in hell....especially for 9 ball. A phenol tip would be tough, but an upgrade..... way different story from a broomstick.