They break and run 76% of the time if making a ball on the break and not scratching. I would say that game is pretty easy for them.
I keep saying the biggest thing for them is making a ball on the break 15-20 times in a row.
Now that we know the number, what are the odds of someone who breaks and runs 76% of the time running 15 racks if they make a ball on the break every time? 20 racks?
Given those assumptions, it's easy to get google to tell you the answer. Just put "0.76^15" (the ^ means "to the power") into the search window to find the chance of a 76% event happening 15 times in a row. The result is 1.6%. For 20 straight, it is 0.4%.
But it is reasonable to object that they are going to have a hard time making a ball on the break every rack, so I would consider Dennis's 60% as about the highest you could expect with an easy table and tight rack. That pulls it down to about one in 2000 for 15.
On the other side, if a player plays bar ball six hours a day, five days a week, he gets a lot of chances. I think the insurance company that guaranteed Earl's $1,000,000 run overlooked the fact that in a tournament with races to 15 there would be many chances to get 10 in a row. And as pointed out above, if you're going for the gold ring, you never play safe or cautiously.