I don't believe a winning player needs such a huge bankroll. You should have about 15-20x the buyin but you don't really need to apply that to each table. I doubt you'll ever be in a situation where you'll lose your buy in at all your tables at the same time.

I have about 100k hands six tabling $50NL, and my largest swing was about $150, that happened once. Normally i'm up enough at other tables to make lost buyins break even for me.