[prole]

These points have merit, yet I know of at least one pioneering effort that was successful: The "Higher Cracking University" or +HCU for short. It ceased functioning a long while back, but at that time it didn't just meet, but far surpassed the expectations of online learning described in these comments.

The link speaks louder than my words: http://www.woodmann.com/fravia/student.htm

Here you had a community that - spent years simply learning - shared their knowledge (for free!) in essays, email, and forum discussions - maintained a level of intelligence in incoming classes by use of strainers (reversing assignments such as http://www.woodmann.com/fravia/strain99.htm) - never needed to meet in person to contribute these great works

It can be done, but perhaps the question is, "why haven't we seen more of these in the wild?"