I think it’s takes at least 8 weeks before you started to become acclimated? And even then it varies person to person, can take up to a few months for some. Seems like a rookie mistake to think you go into the mountain for a couple weeks and be good to go. 2 weeks (cain), and 4 weeks (think that’s the number I saw for werdum) isn’t enough time to get used to it, let alone harness the benefits.
I guess it’s just surprising that high level fighters would overlook something like that. Even more surprised if any of the coaching staff didn’t point this out as well 
Werdum said he did 40 days at a higher altitude
Werdum went for 40 days. Like Jesus 
I was rooting for cain but damn did werdum do his home work. True pro. Respect 
Werdum did everything right, and to the victor go to the spoils. If Cain were half the superhero Rogan claimed him to be during the walk in, then maybe he beats Werdum with a month to acclimate, but two weeks? It was never going to go down any other way. Rafael Cordeiro did an amazing job with Werdum's striking.
In the embedded show, xavier mendez said cain did not even want to come down 2 weeks early and he had to force him.
8 weeks is way too long. 1 month is right around perfect reason being 2 months out you could still be working on conditioning at that high altitude you can't work at full capacity limiting your overall conditioning. Around a month out you should be in complete shape and just maintaining with less rigirious workouts.