The rest of the world does not teach that way, and particularly the countries that have good results in education -- e.g. Scandinavia -- don't. What's with the American exceptionalism? But (as you also hint at) good teaching methods are just one tiny piece in a much larger puzzle.

In fact if anything, my personal impression is that the teaching method itself is among the least important factors; if everything else is in order, kids are going to learn no matter what teaching method you employ.