But made of nasty fast growth pulp wood, cut into thick slabs like an amercan cheese sandwich where they overlap the cheese slices instead of butting them, pressed in glue with enough power to get it vary no more than 1/8" throughout, the stuff is useless for anything else.

I suppose it's been a good sales tool for the OSB products that at least are flat and don't bury 3" splinters through your hand. That stuff holds up better to getting wet than the plywood, it just expands twice it's thickness.

Like fiberglass boats going soft, I'm not quite old enough to be exposing plywood in houses that has delaminated, yet. I'd worry more about the windows(especially windows), doors, trim, siding, stuff like that. I've lived long enough to replace some that which I installed originally, twice....