[jbird]

although i've taken several stats courses in both undergrad and grad school, i (maybe purposely) didn't digest too much of it -- Pete, Troll, and a few others are the real stat guys that can tell you when the sample size will start converging towards your long term winrate, but it isn't 22k hands and most definitely isn't 5k, particularly in a game like PLO where your SD is significantly higher than NLHE on average.

but one thing i can say: move up when you are running good and feeling confident. if you take a hit, move back down. this advice can certainly apply to all stakes, even nosebleeds.