When I went from pure airsoft to real stuff I was a better shot than some Joe Guy off the street, but I have a fuck ton of bad habits and subtle pulls that can only be worked out at the range.
Safety, reloads, general familiarity/ dexterity, sure. But no matter how many times I've watched the Magpul DVDs I still managed to double-feed an AR and then blanked and froze when I had to clear that malfunction.
It's quite literally like comparing Kendo to soldier systems in feudal Japan. They are really only tangentially related.