I think you're correct, but I also think it's a real shame that live performance skills are important to excel at a career that has nothing to do with live performance.
I wonder if there are any careers where you only have to get good at the thing you're doing rather than a bunch of meta-things.
Live performance skills are most absolutely unnecessary to excel in development; this comment thread is discussing how certain people can improve their interviewing performance through the practice of being spontaneous and present. A very helpful trait that some people have naturally, and that others do not.
I think it's great when the practice of some discipline or craft has beneficial effects in other areas of our our lives.