This really isn't so much about pensions retaining good teachers. You could have a defined contribution plan be more attractive than a defined benefit plan.
The main reason that the wise Mr. Rogers is proposing this is that it simplifies accounting, grants control of the retirement plan to teachers, rather than relying on the abilities of the state. The work that must be done to calculated a defined benefit plan is insanely complex, and expensive, and when you are all said and done, may not be much better.
I like the 403(b) style plans because I have more control over them. Also, they are very simple to account for, and budget for. Much of the financial problems that non-profits like schools & governments had stem from defined benefit plans that go wacky in times like this.
Good work, Bill Rogers.