[Harv72b]

I think that the 300 BB rule stems from the kinds of variance you'll see if you use the tight, aggressive style of play advocated by SSH (and followed by most of the posters on these forums). If your playing style is more weak/tight, you'll see less variance and can make do with a smaller bankroll.

When I first started playing, I set my standard at a mere 100 BBs as I moved up. I would not recommend this as I now know that I was fortunate to run well enough that I didn't bust myself out, but my style of play was also a lot less aggressive in those days. Anyway, I first moved up to 2/4 with a whopping $399 in my bankroll, built it up to about $850, and then had a horrible downswing that dropped me to around $80 at the lowest point. That was not fun, trust me.

As other posters have said, a lot hinges on whether or not you're okay with reloading out of your own pocket. If you can afford to do so and don't mind having to, you can rush yourself up the limits a lot faster (basically, your bankroll becomes however much money you have stashed away that you can afford to risk on poker). If you're comfortable playing a little closer to the edge and confident in your playing abilities vs. typical opponents at 2/4, there's no real reason to step back down at this point.