What role does the meat play in this artform, and if it's somewhere between important and critical how do you ensure you buy a good base product?
Or to phrase this another way, do these extensive treatments make a plain or even sub-par piece of meat very tasty?
I prefer primarily filet mignon fairly rare and don't really do much to it, so for me the meat is critical. I discovered buying the whole tenderloin and butchering it myself most often gave me the best results. (At a price point that wasn't ridiculous.)
I do however get the slow cooking part completely. After pan searing a tenderloin roast I bake it at 250 until it reaches 140 internally. Then when I cut it I have a thin crust of seared/medium meat followed by 98% really medium rare. The way we used to bake one at higher temps yielded 1/3 well done, 1/3 medium, and 1/3 medium rare in the center. Definitely inferior for our pallets.
Hat tip to Alton Brown and Good Eats for that method.