Blue
Ravenous Bugblatter Beast of Traal
Whose play are you talking about?
Considering the fact that this change was for the play at my table (of which you have no idea how often I set DCs at 11, 14, 17, 21 or whatever)... I find it funny that you've been trying to claim my change doesn't work for what I've been trying to accomplish.
Now if you're talking about just the average table... sure your math might be right. But obviously my table isn't average. So why you made the claim in your original post...
...using math for tables which are not mine makes me cock an eyebrow at your claims.
I made a bias for discussion based on D&D 5e, where bounded accuracy keeps things near the middle, which looks like your DCs could support.
If you are also skewing the results so that you need to roll something quite different, then that's your responsibility to mention it just as much as it was your responsibility to mention that you are using 2d10 instead of d20 - because that information is just as crucial to having an informed discussion on a forum. Since you took the time to give us your new DC breakdown I had thought your post was complete with all of the information needed to have a fruitful discussion. I see I was mistaken based on what you left off.
So I stand by everything I've said in a general case. If you have more table variations that you haven't told us, that's not my responsibility to read your mind.