I agree.
I have been working on cars forever it seems like. There is tons I dont know and I learn new stuff every time I work on something. I have watched automatics being rebuilt a couple times. I handed parts or tools as the guy was doing the work and I still couldnt tell you what order what goes in there. I know it took some special tools to do it right and gears had to be in a certain way to install a pin or move something.... its a crap ton of stuff you need to know to just get it together.
I make a living working on cars and my car wouldnt be as nice as it is if I didnt do all the work myself but when it comes to a trans, if mine fails I will buy another one cause you can get a good one for under $300 and its around $1400 to have one rebuilt.
Of course at high power levels that changes. When I up my cars power I fulley expect to blow my trans. Then I will spend $1400 for a rebuild cause it will be with high hp parts.