The numbers aren't near being the same and the mass bias will end up in the thumb hole on the TT. What's the layout?

Bob, I used to think the exact same thing, then  I remember seeing a chart where the asym diff continued to grow as the distance increased, whereas I used to hear it would be later and smaller... I can't prove it, but you are right, conventional wisdom used to be the other way around

Bob, total differential is the difference between the Rgs of the X & Y axis. 

You maximize the dynamic instability of that relationship with the pin (x-axis) at 3 3/8" from your PAP in a symmetrically designed ball and it drops as the distance moves away from that number... IE strong migration from ~3-4", moderate migration from ~2-3" & ~4-5" and milder migration from ~1-2" and ~5-6".  This phenomena is less true as we change the intermediate diff.  asyms have their own rules

OP, you will generally see a quicker, sharper break-point out of the asymmetrical ball all other things being equal.

Bob, total differential is the difference between the Rgs of the X & Y axis. 

You maximize the dynamic instability of that relationship with the pin (x-axis) at 3 3/8" from your PAP in a symmetrically designed ball and it drops as the distance moves away from that number... IE strong migration from ~3-4", moderate migration from ~2-3" & ~4-5" and milder migration from ~1-2" and ~5-6".  This phenomena is less true as we change the intermediate diff.  asyms have their own rules

OP, you will generally see a quicker, sharper break-point out of the asymmetrical ball all other things being equal.

And this is the kind of conversation I come here for.

BFD's graph is what I was mentioning from a long while back.