Can we accept less than good/oustanding teaching?

One of the perks of my job is that I visit lots of schools.  In the past few weeks, I have visited several.  In amongst all the great stuff I observed, I was still depressed to see a number of classes where the students were clearly not engaged and the teacher did not seem to be making any effort to correct the situation. 

Most heads/principals would comment that it is impossible for every teacher to be good/outstanding in every lesson.  I'm not sure I agree. 

Professor Brent Davies argues that there are few more skilled jobs around than teaching - and he argued at last summer's NCSL Seizing Success conference that it is more skilled even than surgery.  That's why we need the country's brightest and best going into the profession: it is extremely difficult.
And, of course, it should be a really well paid profession.

Maybe the CBI are right when they argue that schools are in general too tolerant of mediocrity.  To my mind, any lesson where students are disengaged should ring immediate alarm bells to prompt remedial action. 

So - recruit only top people, but insist that their game is constantly at its sharpest.  After all, we can't afford to let surgeons have off days, so it's got to be the same for teachers.

Surely?