I'll add a comment above since it is a bit subtle, but look at this line:

https://github.com/TauLabs/TauLabs/pull/1030/files#diff-3c1ff3789e117137da52548be01cc9f4R238

It rescales the blend factor so if one stick is at 0.85 then the blend factor will be 1. This was to make sure that the weighted averaging sums to 1. If instead I had let the factor range from 0 to 0.85 and use this code above (and made that equation 0.85-rateFraction) then at the maximum rate it would be actually only 85% of the requested rate and would change the stick responsiveness in this mode.