Landa was in Mortirolo always pulling at the front of his group of Aru, slow for him, but working..contador reduce those 50 seconds by sprinting u8and he is an explosive rider) and "rest" at the wheel of somebody..Pirazzi (1 minute), Antón (2 minutes) Hesjedal (1 minute), and 2 minutes as whell at the wheel of Landa before to attack, later was alway Krujkwik working, with 2 amall pulls of Contador.. 50 second is not a big difference in a climb of 45 min as Mortirolo, but anyway as I said contador climbed 7 minutes more at the wheel os someone than Landa, so the performance was not very different in the Mortirolo, or at least no so differet to let Landa attack in a false flat, drop and put 38 second to Contador (helped by Kruijwick as well in that last km),
So I have no doubt the stronger in the Mortirolo was Landa, despite Contador climbed 50 second faster, and did a performace equvalent to be 30 second faster than Landa, but the difference in getting tired was much more for Contador than Landa that those 30 seconds difference in performance.
Landa did not attack as Contador did next day when Landa had a problem.
If Landa attack att he botton of the Mortirolo could have be a big difference in Aprica, but he was just allowed at the end to get the stage.