ATM: Modified Stroke Length for Undersized Tool?

[Adam Rosenberg <adamr@synopsys.COM>]

Hello again,

I'm working with a 9" tool on a 10" mirror and I think part of my problem
is trying to adjust my stroke to account for this difference.  When I do a
1/3 TOT stroke do I allow the center of the tool to traverse 1/6th of the
mirror in either direction or do I extend/contract the stroke to account
for the slight size variation?  

Thanks,

Adam R.