Tenure is intended to protect teachers IN classrooms from administrators who've never set foot in one. Administrators love to 'implement' new ideas. Even if what has been happening isn't broken, they like to do this. Teachers who won't go along with every crazy notion are labeled "uncooperative" by such administrators when they continue doing things the way that they KNOW in their hearts is right and good for students.
Trust me on this one-- I've been that teacher (yes, post-secondary, but my mom was that teacher in elementary). Administrators are frequently out of touch with reality to a fairly stunning degree. In their desperation to do "something" to "improve" things, they'll try pretty much anything; but seldom long enough for it to make a real difference either way.
Out of touch administration is certainly not unique to the profession of teaching. In fact, I'd say it borders on being ubiquitous, yet no other industry comes to mind in which the ability of an administrator to fire a subordinate proves to be so problematic. You seem concerned that the wrong teachers would lose their jobs, while I'm concerned that hopefully many of the right teachers (finally) would.
So what makes teaching (without research) so different?
Yes, you might have bad managers in a profession other than teaching. However, are you as a middle manager given a poor curriculum based on national standards which might have little to do with your actual work to supervise your subordinates/co-workers and then judged based on THEIR performance? Keep in mind that you can not fire any of your co-workers, they have more protections and job security than you, they have little to no incentive other than intrinsic motivation and perhaps parental support/expectations to actually perform. Nothing will happen to them if they perform poorly, yet your job evaluation depends entirely on THEIR performance.
And don't try to tell me that great managers would find a way- great managers succeed by getitng rid of poor workers and replacing them with more productive ones. Teachers do NOT have that option.
Also, it's not really that hard to fire bad teachers, even in unionized states. Due process might be required in order to ensure that a teacher is not being fired for teaching evolution in some backwater East Texas town, but it is doable despite what the media would have you believe.
