Originally Posted by
HillRider
First, 5-speed dropout spacing was 120 mm and 8/9/10-speed road dropouts are 130 mm (MTB's are 135 mm) so the dish increased isn't nearly as much as you think. Second, spokes, hubs and rims are much improved in quality over what was available in the 5-speed era so wheel strength isn't nearly as much of an issue.
I think the point was to use the modern width of 135 mm, but with a shallower cassette body holding just 3-5 sprockets, allowing the drive-side flange to be moved out by perhaps as much as 20-25 mm.