I think the idea of him lacking the mental ability to win the TDF is more or less a moot point. Ullrich wasn't exactly the strongest guy mentally but he still won a tour, it's about his mind + legs being strong enough. Personally I think he's talented enough to win this tour regardless of his mentality. While today showed his willingness to attack his time loss in tuesday's stage showed his mental fragility. Personally I think today's victory might have strengthened him mentally and I definitely think he's strong enough to win any classics or tour in which his legs are the best. However I also believe he's not yet strong enough to win when he's not the best, or even when he's equally strong as his competitors. But he's only 26 his best years, both physically and mentally, are still ahead of him.
Edit: Also I think that the answer to the original question has to be yes he has the ability to attack in order to win. I think in the past he has shown a willingness to attack both in the TDF and LBL, I simply don't think he was strong enough in the stage to Luz Ardiden and he was afraid to drop his brother on the stage to Plateau de Beille. I think his problem isn't an unwillingness to attack but the fear of blowing himself up by going for it with other riders on his wheel that all riders seem to have (apart from maybe Contador who seems to know his own body to an impressive extent) combined with the lack of a true explosive jump that would allow him to drop the others with one swift move, which is more physical then mental.
But I guess tomorrow we might get an answer if he's recovered enough he might well attack again showing his true spirit (then again he might not be good enough so it's hard to predict right now).
Edit: Also I think that the answer to the original question has to be yes he has the ability to attack in order to win. I think in the past he has shown a willingness to attack both in the TDF and LBL, I simply don't think he was strong enough in the stage to Luz Ardiden and he was afraid to drop his brother on the stage to Plateau de Beille. I think his problem isn't an unwillingness to attack but the fear of blowing himself up by going for it with other riders on his wheel that all riders seem to have (apart from maybe Contador who seems to know his own body to an impressive extent) combined with the lack of a true explosive jump that would allow him to drop the others with one swift move, which is more physical then mental.
But I guess tomorrow we might get an answer if he's recovered enough he might well attack again showing his true spirit (then again he might not be good enough so it's hard to predict right now).