Doesn't that heavily depend on the teacher though? I don't disagree with you in principle, but couldn't the reason so many people try to dictate the best way to teach is because there are a lot of bad teachers?
If a kid brings home a bad report card - Parents often blame the teacher. Obviously, their kid is great, the only reason they are struggling is because of negligent or poor instruction.
If a kid brings home a behavior citation (i.e. teacher/administration called home and said their kid was poorly behaved) - Parents may or may not recognize themselves as a contributor to that poor behavior.
But for the teacher, it doesn't really matter. If there is one poorly behaved kid in the class, it's going to make it harder for that teacher to instruct every single kid.
It often seems that the problem isn't a glut of "bad teachers", it's that the structures placed around the teachers all too often seem to be set up for them to fail. It's no surprise then that 40%-50% of teachers quit the profession entirely within five years http://www.edweek.org/ew/articles/2012/05/16/kappan_ingersol...
I'm not knowledgeable in the industry, which is why I'm asking. I know that for most industries, standards and structures are in place to protect damage from the worst people, but can definitely inhibit the best people.