I've been fine over 14k ft with one day to acclimate before and I've also had headaches at 8k ft. I've also done 3 14ers over 3 days only to get AMS on the fifth day while lower at camp. AMS is a fickle mistress and one of the banes of my trips. For me, it's always been very hard to know when it'll rear its ugly head.
Thanks for the info Bob. I want to go back to try the green route.
Due to the difficulty all of us were having, we only did the yellow and blue routes to get off the mountain as quickly as possible.
I am hoping my difficulty was due to lack of sleep and acclimation and not an indicator of my fitness level (I've been dealing a bad cold or allergies for 6 weeks now and haven't been able to train).
