changing the curriculum is what ya do when the teachers can't learn it cause then they can't teach it and you cannot fire em
I know there are some really dumb teachers, but there are really dumb EVERYBODIES. One of my friends was cleaning out a cabinet with old "ditto sheets" of what her students had to learn in years past. She called them "practice sheets."
Regardless, she could not believe what the kids USED TO learn and what they were presently learning (dumbing down, and it wasn't her/their fault) - long story.
Tenure was created for due process - fight fair was all it was intended for - geez, most people do not have the freedom - screw up, bye, bye.
I understand your example, I do.
I keep going back to the fact that teachers' hands are tied more often than you know.