I don't know how exactly it was calculated. But you might be looking at the wrong side of the equation. In any case, the guy first posted that it was a 2% chance for a million rolls of dice to wind up ahead, then someone else pointed out that he was wrong on an order of magnitude, and the first guy then recalculated it at 5%, and days have gone by and no one has challenged that figure. He also posted how the house edge in Baccarat is lower than craps, so it must be more like 7% for the million hands of Baccarat. These figures are based on what percent COULD be ahead after a million hands, not would. I didn't play 1M hands obviously in just 8 trips, but I am that could.
The other thing that people keep bantering about is my statement of that quitting while ahead is the ONLY way to win. That is such an obviously true statement that I think it eludes people what it means. Instead, they get bent out of shape extrapolating statistics. Try quitting while behind every session see how far that gets you.