While this thread isn't about Evans, I'm going to chime that he was perfect. The only opportunity Schleck may have missed during the Tour was in the Pyrenees, but I highly doubt he would have gotten away from Cadel with time to spare for the ITT. I think that if he could have made a large dent, he would have.
I'd vote that Andy lost it in the early season where he should have been working on the TT, or the season before that, or the season before that...
Its just not good economics to work towards adding 90 seconds to the capacity of a top percentile climber, as opposed to improving the weakest skill (and that steeper part of the improvement curve). I can't really articulate what I mean, but Schleck had a choice between trying to be such a dominate force the mountains to buffer his time trial (which is unrealistic against the best of the best competitors) or sacrificing some of that to be able to hold is own in a TT, and he obviously chose wrong.
Hindsight makes things very clear, but this sentiment seems common when discussing Schleck's chronobilities.