[Glenn]

You did this incorrectly. First of all 3SD's is 99.7% confidence, so the chance of a -3SD event is only .15%. Secondly, (and more importantly) finding the number of hands where a 3SD downswing gives you the biggest negative result is not the correct way to approach the problem of "how much can I lose in a row". This is similar to the bankroll method Mason uses in GTaOT and it is flawed. The problem is much more complex because there are many sets within the set of data, but there is also correlation between them. Search brucez's posts for an actual detailed explanation. The easiest way to analyze this problem is through simulation which can be done with relative ease in excel.