On Wimbledon 2012 Federer played better and on Cincinati Djokovic was exhausted because he was playing 4th week in row, on Olympics, Toronto than Cincinati.
Thats why Fed skipped Toronto - to rest himself and prepare for Cincinati.
I think that Toronto and Cincinati one after another without week rest, is very bad because both tournaments are from Masters 1000 series.
Roger is very smart in his schedule, he is not younger anymore, so it was actually a good desicion for him. Djoker exhausted? I'm not sure, it was his 3rd week, not 4th, but I know he didn't play his best at that set. Yea both are M1000, but we know..Toronto was not exactly a tough tournament last year..considering almost all top players didn't go/tank early, but I won't discuss about it. Look, I actually enjoy Djoker-Roger matches, are very entertaining..good rallies and good shot making, except when Roger chokes of course, but credit to Djoker to being very strong mentally(and so fuking lucky sometimes too). I hope they meet each other in the final, would be an interesting match to see.