Probably.It was covered in class, just having a real life scenario was a wee bit different than something that was staged, where you were expecting SOMETHING to go wrong, with an instructor watching you, in a training cave with good viz, knowing the drill could be ended at any time if you exceeded your comfort level. Maybe I'm the only one who would react differently and everyone else would be like "Oh I got this, I did a valve drill at Ginnie Springs once".
I can't speak to what everyone is predisposed to do, but I know when I've had a reg failure, the first priority and action was to get on the line, then work the reg/valve problem. But perhaps that's because I'm generally a "why?" kind of person who puts more focus on conceptualizing why something covered in training is important, rather than just running through drills, procedures and processes. Knowing the why ensures you prioritize things properly when the **** really does hit the fan and/or when you encounter multiple issues with potentially conflicting priorities.