Good win for Fed - this is the kind of match he's been losing in recent years. Good to hear Davydenko played well.
He played great indeed
Very quick (I was not sure he was still able to be that quick), going for his shots, very few unforced errors until the end of second set : at that moment he had a problem with his knee and made a few unforced errors (but nothing like when he really loses his game, including against Fed at Aus open 2010, it was only a few unforced errors) until the beginning of third set ... but he went back with a lot of motivation and quickness after saving multiple break points in the beginning of the third.
I never saw Federer playing awful in that match, but he needed time to raise to Davydenko's level (what was great there is that it showed that still he had great desire for the game). And even if Davydenko went from 4-4 to 6-4 3-1 these games were tight.
I knew that with some confidence Davydenko could still play very well but I'm mostly surprised by how quick he moved in that match : against Gasquet he made great shots but he had more time to prepare his shots, I was not sure he could still play with that unbelievable rhythm, I thought he had lost a part of his movement.
As for the confidence clearly he had no fear at all going for his shots in this match : that's what should give him the best feelings.