You sound like a professional welder to me - you've been to a class. I tried TIG on an aluminium roof top box I made for an old LandCruiser about 25 years ago with a proper welder helping me. I've never tried TIG since and it's still a bit of a mystery.
Not a professional , not certified just trained at the school at hard knocks.
Out of high school I hard a job as a sandblaster/Painter at a welding and fabrication place that that made Braun commercial washing machines for Braun and then they did all the finish work.
Welders there would teach me during breaks on scrap so I had a basic understanding.
A couple years later I bought a new Lincoln tombstone ac welder for my home projects.
Then every job I held there was times I needed to weld i would try some more.
I had to repair some aluminum guards on equipment there so we bought a tig and I kind of learned some from a Lincoln web site. That was a challenge getting that to welding point and if you were not careful and keep moving the puddle would fall thru. From there I was doing repairs on stainless sheet metal some.
Not anything I would brag about for quality but got better as time went on.
I have one at home because there was one for sale used, pretty cheap and I couldn't pass it up.
Still have the old lincoln, a hobart ironman 210, A hypertherm 45 plasma and the tig I think is a miller.
I kind of relate tig to oxy actelyne as far as some of the skill needed. You need to heat the metal to melting point and keep the torch moving or you have a mess. And both can sometimes be done with or without filler metal.
Bill