On the new BionX controller code 0008 extra assistance range

A goes from 1 to 4

B goes from 10 to 25

Does any one know why there are 2 different settings A and B. What does the B setting do?

I was also wondering if any one has played with the 0007 Assist Sensitivity range

goes from .1 to 4

Is ther some kind of ideal setting?