Yes, the ways in which it can be used are huge. Some of the obvious ones are to teach someone to code and play the sequence later anytime. CodeTable supports collaborative editing which makes it even nice. Other use can be to ask someone to solve a problem and watch them how they approach it. And there could be many more!
Yes. Learning Python at the moment, and after I do a practice problem I often look at the writer's solution to the problem. I would find it much more informative if done in this way, with comments saying why he's doing what when he does it.