Thanks for your comments and the thread link. Since I play limit 5 card draw as well, I just ran through a few calculations based on
pokerstars rules for $3/$6 limit games using the 300BB rule to see how it stacked up, and compared it with doubling the rule to 600 (as suggested in the other thread).
One definition: I call
maximum exposure per hand the theoretical possibility that each betting round for a hand is raised to its maximum.
maximum exposure per hand
= sb betting rounds * raises cap *sb
+ bb betting rounds * raises cap *bb
PokerStars, for example, has a raises cap of 4 bets.
$3/$6 LIMIT HOLDEM
300 rule
Min Bankroll: $1800 (300*6)
Minimum Buy in: $30 (1.7% of indicated bankroll
IBR)
Suggested Buy in: $120 (6.7% of IBR)
Raises cap is 4 (e.g. PStars), 2 sb betting rounds and
2 bb betting rounds then
max exposure per hand = $72 (2*4*3+2*4*6) 4% of IBR
600 rule
Min Bankroll: $3600
Minimum Buy in: 0.8% of IBR
Suggested Buy in: 3.3 of IBR
max exposure per hand: 2% of IBR
Contrast with Limit 5 Card Draw
With limit 5 card draw, there are only 2 betting rounds so running through the numbers -
300 Rule: max exposure per hand: 2% of IBR
600 Rule: max exposure per hand: 1% of IBR
Theoretical Profit @3$/6$ Limit Holdem
People say generally accepted theoretical profit might be 1 to 3 bbs per hour (see
http://www.fixedlimitholdem.com/winning_low_limit.htm for example).
So, say, I play for 2 hours a day, 4 times per week, my profit per week
should be 8bb, $48, and 2.6% of 300 IBR rising up to 24bb, $144, and 8% of 300 IBR. For the 600 rule, the percentages would halve to 1.3% and 4%.
Overall
It is possible, even on a sane table with no maniacs, to max out the betting if several big
hands are dealt and the flop has something for more than one player. The 300 rule for LHE might just be a little risky for me potentially putting 4% of IBR in play on one hand - good if it wins but meaningful if it doesn't.
For L5CD, the 300 works fine at 2% and compares well with accepted metrics for how much bankroll risk should be taken with cash and SNGs NLHE table buy-ins.
I will be using the 300 rule for my limit 5 card draw games in future.