I've been saying for a while now that 'something happened' in 1985. Things changed.
It hadn't occurred to me that Goldin and Katz's timeline in The Race between Education and Technology corresponds directly to mine.
Goldin and Katz find the schools somewhat abruptly ceasing to function as producers of greater equality via educational attainment in the early 1980s.
I find the composition journals abruptly ceasing to function as producers of useful observations re: teaching students how to write, also in the early 1980s.
I don't think that's a coincidence.