Okay.
Apparently I have botched the implementation of this model so badly OR I have misunderstood the model to the point that this thing is, as stands, completely unusable.
My worst nightmare is true -- I've modified things so that right-triangle rules can be handled the same way as isosceles triangle rules, but there's one firing position that produces a curve well above the average.
This can't be right. It's got to be half the volume on each side, otherwise these results can't possibly exist in some cases. Having said that, I'm going to recode it tomorrow that way.