Black Powder Command Rolls

It's been a while since I've mentioned the Black Powder rules on this blog. I've enjoyed developing my own rules, but I still regard BP as my favourite commercial set. My reason for posting here is to pass on some info which might be useful to players. Many may already be aware of this slight inconsistency in the rules but I reckon many will not - I first read about it over a year ago on another gamer's blog and I didn't really take it on board then.

Anyway, browsing the net I rediscovered the appropriate post on Craig Welter's wargames blog, Adventures In Miniature Gaming. I think most BP players (like me) assume without thinking about it that when making a command roll, getting one move is more likely than getting 2, which in turn is more likely than getting three. This would surely be logical. But as the rules are written, getting 2 moves is actually half as likely as getting 3 moves with a normal Staff Rating of 8. This is because the only way to throw 2 less than 8 (to get 2 moves) is by making a 6 with 2 dice, which gives you 5 chances out of 36. But to throw 5 or less with 2 dice (to get 3 moves) means you have 10 chances out of 36. Similar problems arise with other SRs. Craig's post shows all the probabilities. 

I can only assume the original rule is designed for ease of remembering. I have also seen it suggested that this greater probability of 3 moves is how the authors intended things to be, but for me at least this intention doesn't really make sense.

Craig has a very reasonable solution which works well - see his post. I will be using Craig's fix in future, which is straightforward. An alternative might be to get 3 orders only if one throws exactly 3 less than the SR. If you throw less than this, roll again.

Thanks to Craig for publicising the problem and suggesting a solution.