...(a 7 dice difference in dice pools)...

Apologies again, but that is the math error. You can't simply compare the single bell curve of the difference in dice pools. You need to compare the overlapping areas of 4 different pairs of Bell Curves, 8 total, and then compare the % change between the two scenarios.

The bell curve of the difference in dice pools is absolutely not, in any way shape or form, an accurate representation of the probable outcomes of an opposed test. To illustrate, using your Difference only model you have the same outcome of 0 v 1 as 15 dice v 16 dice. 0 v 1, the 0 will never win. 15 v 16 is slightly less than 50%.

I realize being told on the interwebs that you're wrong isn't ideal. I do sincerely appreciate your time and energy being spent to respond, and the time you spent in creating the game. Thank you, again for your time.