There really isn't a difference. It's called being on your own & gaining situational awareness. It was never just about teaching stalls. You had to constantly be aware of your students abilities, and where you were going if the engine quit. Where were you going on a cross country if your student became ill? What happened if a thunderstorm popped up and you couldn't get back to your airport? Seems like simple stuff now, but to low time guys who haven't made a lot of decisions it's can be complicated.

I put my instrument students in IMC all the time. I wasn't teaching them to fly under foggles. I was teaching them to fly in IMC. Never did I intentionally, but I did get into ice or near thunderstorms, & it taught me a lot.

I had plenty of 500 hour puppy mill FO's when I was an RJ CA. We got along great, but many of them lacked the basic situation awareness to really operate the airplane in a 121 environment. One flew me right through the localizer on a visual approach to parallel runways in 10 SM of visibility because he didn't have a Flight Director to follow. I should have never let it happen, but I went heads down for a minute and he's 8 miles out doing 250 kias blowing right into the path of another airplane. Others couldn't even do a visual approach without an ILS to the runway, even if they had a PAPI/VASI. And don't even get me started on when we were down in Mexico!

I had over 1100 hours when I got hired at my regional, and I don't think that was enough time. It took several months on line before I was comfortable. I strongly support the ATP requirement. Your Pt 135 experience is a great way to cut your teeth too, and you have to have quite of bit of time to be a 135 PIC. We need to shut down these pilot puppy mill operations, because they continue to hurt this occupation.