Didn't andy beat him in 3 at USO. ?
I find it interesting that you didn't quote my whole message that contained the important reasons. Not sure if it was deliberate or not.
Some of the reasons for Andy winning at the USO are :
1. Andy had at least 1 days in between to rest and recharge his energy level
2. Andy had time to practice with someone with a similar style as Raonic, and talked strategy with Ivan to prepare on how best to play Raonic after Ivan scouting on Raonic previous match
3. Andy did not have to play Doubles and Singles the previous day.
4. Andy himself commented that his passing shots today are not as good as at the USO so Raonic was able to advance into the net more today. Now this may be related to the fact that his body is tired from Tokyo previous round matches less than 24 hours ago, as well as the accumulated impact on his body over a long Wim/Olympic/USO season.
I suddenly realised today that non GS tournaments where one has to play 5 matches in normally 6 days with a day break between the first and second round and then 3 consecutive matches from QF onwards is a totally different beast from GSs where one plays 7 matches over 2 weeks with at least one day in between to rest, practice & prepare. They are like chalk and cheese and can not be properly compared.