Lecture halls for grade schoolers?

Education "reformers" love to take their shots at teachers. Sure, they say they respect the profession and how hard it is, but then they turn around and make sound as if anyone can do it from anywhere and with with little training. One of the lead "reformers," NY Mayor Michael Bloomberg recently claimed he could solve all of our education problems:  

"And I would, if I had the ability - which nobody does really – to just design a system and say, ‘ex cathedra, this is what we’re going to do,’ you would cut the number of teachers in half, but you would double the compensation of them and you would weed out all the bad ones and just have good teachers. And double the class size with a better teacher is a good deal for the students.”

This also goes hand in hand with his comment that teachers come from the bottom 20% of their college classes. Matthew DiCarlo explores this concept here.

And people wonder why it's becoming harder to recruit and retain teachers...