I just completed the Eastern Sierra Double covering almost the same roads... It was beautiful up there, and they are right about the weather being unpredictable, but I would not worry too much as they are offering to take all your spare gear in SAG vehicles to the finish.
Believe me when I tell you that the scenery will keep you diverted from any pain in your legs or lungs!
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Women think they're so clever because they can fake an orgasm for the sake of a relationship, but men can fake a whole relationship for the sake of an orgasm.