Both Djokovic and Federer have looked WAAAY more impressive than Nadal. I don't REALLY understand the lack of confidence by Nadal in early stages of Wimbledon. He's reached 5 finals, WON the title twice and is the second best grasscourt player of this generation. Yet he persists with his pusher, defensive tennis in initial stages and moves like it's ice, rather than grass.
What does he need to get more confidence? He should be a natural by now. Djokovic, in contrast, looks like a man who believes in his abilities on grass courts, even though he's won once and made the final only once..