[sdenton4]

The ratio is really what matters more than absolute numbers; it tells us where the bottleneck is (supply or demand).

If the STR is 2:1 and you've got 1000 teachers, it means you've got 2000 students. If only 5% of teachers are good (see: sturgeon's law), you've still got competition centered on the student side, as 2k students fight to get into the classes with the 50 good teachers.

[MontyCarloHall]

Ah, I get your point now. In my hypothetical example, you could still have those 2000 students enrolled with only the 50 good teachers. The overall STR would still be 2:1, but most of the teachers would have no students, so the effective STR would be 40:1.

The main thing distinguishing online education is the ability for students to all flock to the good teachers and completely abandon the crappy ones.