If your argument is that we should purse some kind of standardized metric for teaching effectiveness, and that it might take the form of a standardized test, I'm with you.

If your argument is "nothing could be worse than the way it is today", I strongly disagree. More than 70% of Americans are satisfied (or better) with their own local school. High-stakes testing can easily make schools worse by disrupting curricula and damaging incentives for teachers. If we're going to focus our efforts on the school systems that are in crisis, there are probably better interventions.

Measuring teacher effectiveness is a real problem that needs real work, but in the interim, primum non nocere.