> This would imply that education degrees make their recipients better educators. There is no strong evidence of that.

This is orthogonal to what he is discussing; he's just discussing the relative pay picture (in-profession vs. out of profession) for one who holds such a degree.

> > The fact that teachers with master’s degrees are no more effective in the classroom, on average, than their colleagues without advanced degrees

This is -further- orthogonal and off-topic, because we're not talking about the relative merits of graduate education for teachers compared to bachelors degrees.