http://sites.google.com/site/aleromo...xterior/wheels
Not sure... I mean as you increase the width of the wheel, with the same offset, both the inside and outside of the wheel are wider, obviously. The thinner the wheel the more flexible you are on offset. If you use a lot of positive or negative offset on a thin wheel the edge of the rim/tire would still have some room before meeting the edge of the fender or the inside suspension.
As the wheel gets wider the range of offsets thins.