I can't believe this post, suggesting new players should 4 table 6max. We read all over the site to work on mastering your game before adding tables, but here he's saying that it should be pretty ez, their goal should be 10k hands a week? Just think that's horrible for a new player to read. They'll get there when they're ready.
About the % of br on the tables issue - you can take that as a license to be ridiculous, ie. $200 br, 20 buy-ins = $10 - so I'll play 10NL - since I'm good, I'll 20 table it, meaning I have 100% of my bankroll in play. No matter how good a player you are, even if it's not technically -EV, I think it's stupid to do. Ofcourse this is an extreme example, but I think players should decide a % they can live with as far as risk management and stick to it - I currently don't play with more than 10% of my br in play at once, but I can certainly see that changing to where I'm comfortable up to say 25%. Just depends on the person.