I was taught before I soloed. In fact loops, rolls, hammerheads and spins were taught before solo. (Many of us were underaged so it was fun and gave dad something to do while we were waiting for the age requirements.)
I only instructed advanced courses and they were to teach unusual attitude and spin recovery to corporate flight departments. A Beech E33C was used.

One chief pilot of a large aerospace manufacturer's corporate flight department that had never been inverted did well, but asked for another flight just to become more comfortable.

I'm old, all of this happened in the 70's and 90's respectively. My kids don't want to fly and I've been out of the training business for years, so it'll be interesting to see what others input.

Chris...