Canelo's stamina is ruined (like Margarito/MAB was) cause he left high-altitude early

It depends, with the way many athletes misunderstand the physiological response then a placebo is the best they can hope for, with detrimental effects being a distinct possibility.
The most proven way to get benefits from it for sea level performance is to train low, sleep high. Intensity is paramount to improving or maintaining central fitness, and you simply can't do it at altitude. Spend too long at altitude and you lose lean mass as well. If you train at sea level you can maintain intensity, then by sleeping at altitude you get the peripheral benefits. But those benefits only last a couple of days, if you leave high altitude a week beforehand you've lost any benefit.
If you were fighting at altitude it would be very important to acclimatise by training at altitude though.

 

Canelo will lose mayweather for life. Gooooo mayweather!!!!

 

If Canelo is so much better why does he need to train at a high-altitude when Floyd doesn't even leave the city and trains every fight in Vegas ..you either have it or you don't ,it didn't work for Shane so why would it now. Floyd is not ready to lose this high profile lifestyle ,Hard work dedication!!!

 

No need to get silly now

 

already making excuses for why hes gonna lose?

 

what fight is next???