I've known various portrait photographers that use a six-shot set or something very similar like a roll of 120 in an RB. Each shot having a different pose or adjustment to the lighting, wasn't a bunch of repeats.

I don't think machine gunning is what Abell/NG necessarily did though. My impression from the video and from other places where I've read Abell"s suggestions is more about planning, experimentation, and refinement.

Machine gunning, IMO, is when somebody doing a group photo just holds the button down for 5 seconds on fast auto-advance just to make sure they get a usable one of the group saying cheese. One shot of "say cheese faces" is bad enough, doesn't improve no matter how many shots you take.