I'm a craps player. When I'm in Vegas there are always people at the table who try to set the dice and only end up holding up the game. I do, however, know a guy in Vegas who can do it relatively well. It takes an absurd amount of practice (far more than it's probably worth) and you need your own table. More than just changing the numbers on top you need to be able to repeat a perfect toss that hits the table then the wall then the table again, all the while keeping the dice together through the air and minimizing the spin. While rolling the point on your first shot is difficult even for someone who's been doing it for years, you can certainly significanly reduce chances of crapping out.