Re: 7 Wimbledon Titles. Who is Real King of Grass?: William Renshaw vs Roger Federer?
you made a strawman with "fast grass King" and a "slow grass King" and want to move discussion in that direction. brilliant strategy. the fact is - there were no grass specialists for federer at all to compete when he was winning wimbledons, while there were bunch of them for sampras in his time.
not to mention you never cared to explain logic how the era with grass specialists is weaker than era with no grass specialists?!
and because I'm in a good mood, free hint for you: grass is grass, physics of the grass game didn't change at all, the ball still stays low on slices, ball still bounces irregular from time to time, it is still much harder to move than on hard courts and clay. for the real reason for play style change (no specialists) you need to take a look at strings and rackets.