I don't know much about heat treating cause I was never involved with it. I know you can change the color of steel by heating it to different temperatures in an oven.
I'm more curious about the Hobart school. I was expecting you'd be giving updates on what you were learning and new techniques they've shown you but you've hardly said anything other than that you really enjoy it. I think it would be of great benefit to the users of this forum who want to improve their welding skills.