The article doesn't propose a pure-virtual model, for exactly this reason. But imagine that for your favourite Harvard class, there is a corresponding regular meetup taking place in your hometown (and maybe other associated social events), and an online forum where the 20,000 people taking the class can discuss what's going on, seek help, and so on.
In my hometown there were only a handful of smart people my age.
In fact, it wasn't till I got to college that I understood what smart even was. Till then my sample had been so small that I couldn't distinguish smartness from the idiosyncrasies of the few individual smart people I knew.
It's true that what I propose is not an optimal solution for the very brightest students. For such people, if they wish to develop there really is no choice: they need to move to the centers of world learning, and seek out the brightest people they can, to challenge and teach them.
But for people who are merely bright and interested, and perhaps not able to afford Harvard's fees (or otherwise gain acceptance), what I propose might have some considerable value.
