Quantifying Great Teachers?

I'm reading an interesting report today, about a study of how great teachers help their students achieve:

Right away, certain patterns emerged. First, great teachers tended to set big goals for their students. They were also perpetually looking for ways to improve their effectiveness. For example, when Farr called up teachers who were making remarkable gains and asked to visit their classrooms, he noticed he’d get a similar response from all of them: “They’d say, ‘You’re welcome to come, but I have to warn you—I am in the middle of just blowing up my classroom structure and changing my reading workshop because I think it’s not working as well as it could.’ When you hear that over and over, and you don’t hear that from other teachers, you start to form a hypothesis.” Great teachers, he concluded, constantly reevaluate what they are doing.

Superstar teachers had four other tendencies in common: they avidly recruited students and their families into the process; they maintained focus, ensuring that everything they did contributed to student learning; they planned exhaustively and purposefully—for the next day or the year ahead—by working backward from the desired outcome; and they worked relentlessly, refusing to surrender to the combined menaces of poverty, bureaucracy, and budgetary shortfalls.

What Makes a Great Teacher?