I don't think Rafa is weaker than Andy mentally, but I think he does rely more on confidence.
That's what I mean. I wasn't suggesting that Rafa is mentally weaker, but I do think he is the most fragile in terms of his self belief and self confidence. I mean, look at the results he has had over Federer, and yet he still considers Federer better than him, or he did when he was last asked. Some would say that is just respect, but I don't know. To my mind it is lack of belief in his own ability, or total bluff, and I don't think Rafa is good at bluff. I think Rafa is someone who needs wins to build his belief in himself. I don't think he is so good at believing when the results just aren't there.
What I think Rafa has done over the years is to achieve in spite of being insecure. I'd bet really good money that no one would be more surprised than Rafa that he has won 11 slams.
As far as Andy is concerned in terms of confidence, I really do think he started out as a very confident player, but I think those major final losses chipped away at that to a point. What I think he has done, maybe with help from Lendl, is rediscover that confidence again.