I agree with Vino Attacks on this. In my observation, Contador's gearing/cadence started to change around the time of the Zoncolan a while back when Sram introduced their Compact + long cage derailleur and 32 or 34 sprockets. That was a blessing compared to being over-geared on extreme climbs like the Zonc or Angliru. But I think Contador started to turn a lighter gear in general at that time. Not that there's anything wrong with that in terms of efficiency, in theory. But for his danseuse pedal style, I think it became a bit of a crutch and cost him speed and power. Coincidentally (?), his climbing and punch began to decline against his major rivals. This year, in my opinion he is visibly turning a slightly heavier gear again, his power is back and he looks more graceful to me, as well.