Accordiing to kelly, you will double your bankroll every 3590 plays if you have a 2% advantage. (Is this true?)
So if you play 1000 games a year you get a paycheck every 3 1/2 years (maybe)
I guess this is a standard deviation question.
How many games does it take with a 2% advantage before you know you got'em by the balls? If ever!!