The odd thing is how many points Federer had the upper hand and came into the net behind an aggressive shot, but Djok can track it down and hit a passing shot. The risk/reward quotient for an attacking player is simply too low where the aggressor has to go for high risk shots and the defensive player simply has to put them back in play with placement.
As for your point on physical style of play, Djok doesn't visibly seem any worse off for it even after years of sliding on hard courts.
It's good for Djok and he deserves it, but unfortunately it's not good for tennis. Most fans (I am guessing) like to watch because they are entertained and want to see spectacular shotmaking and variety. The grinding style of play will just lose spectators for the sport.
Head LM Rad MP, Wilson Blx 6.1 95 16x18 w/ RPM Blast, 4 1/2 grip.