I don't think at the moment that anyone is planning on being from anywhere too far from others, though it is a fair point that everyone probably won't be awake or asleep at the same time. Either way the idea is pretty free form so I don't think the extra slots in the CS will be necessary. 

If you actually put in the hours of work your knowledge/ability in the waking world would change, but for the most part people will likely be thinking "I wish I could do karate/fly" and then (while sleeping) having that ability. It would take an approximately identical amount of time to truly [i]learn[/i] something.