Yep. I've had it happen right in front of my primary care doc and my most recent neurologist. They immediately ordered a magnesium check (normal both times), and otherwise were not concerned. Neither am I. The twitch doesn't hurt; it actually tickles a bit sometimes. It doesn't get in the way of doing anything, and isn't in and of itself a sign of an impending medical/health apocalypse. As for gaps, those emerge as we get older, as subcutaneous fat is lost, and muscles age. Unless the muscles of your entire hand are simply wasting away, you can't button a shirt, sign your name, handle a fork, brush your teeth, or type, you've likely got nothing more than a BFS symptom.
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