When is a MOOC not a MOOC, but just an online course? When it doesn’t scale.
Another possibility, as you are taking the long view… learners will already know how to learn this way, because these skills will be developed by the time they are including MOOCs in their personal learning network / environment.
It isn’t happening very fast, but there is a growing recognition that there are simply too many learners and not enough teachers to go around. That model isn’t scalable. Guided and self-directed learning following the model of the original MOOCs like CCK08 have no problem accommodating 1000s of learners without reliance on direct interaction with TAs and faculty.
Edit: Sept 23 – What do we mean by TA? Are we talking about the same thing? There is certainly a place for “someone” to help self-directed learners but the exact nature of their role needs to be defined. In most higher ed situations, TAs are still focused on subject content. Informally they support learning, as well. As proposed to support MOOCs, it isn’t clear yet how the TAs will be selected, trained and support the participants.