I edited one and reversed steps 1 and 2 so my Inverter is on before the Battery switch to prevent the Master Caution. I was gonna ask if that was legit or would blow up the jet or something.
Tech Data only has you start the APU with the inverter off in extreme cold temperatures. The Master Caution light was a bug in 1.1.1.1 and has been corrected in DCS World.
I say the most accurate startup procedure is the one you can do that gives you a 100% functional aircraft in the shortest possible time. In real life, they do a lot more and coordinate with ground crew to verify movement of control surfaces and such but we don't have that in the sim so some allowances have to be made in terms of "realism" and "accuracy."
It's not about the shortest possible time, that's how pilots forgot switches and call Red Balls only for us maintainers to fix their problem by turning a switch ON. But you are correct, we do a lot more than just flipping switches, the checklist I made and referenced above has an appendix (A) showing the most of the flight control checks and how we accomplish them with the pilot. There are a few items that we check on the ground i didn't include because there isn't a way to verify in DCS.