In my experience (learning aluminum TIG at a hobbyist level) having a "steady hand" is all about setting things up from the start so your torch hand always has

In my experience (learning aluminum TIG at a hobbyist level) having a "steady hand" is all about setting things up from the start so your torch hand always has something stable to rest against. There will, of course, be people on either extreme who either have a stable enough hand that they don't need to rest on anything, or who have hands that are so shaky that propping against something doesn't help, but I think for the ordinary able-bodied person it just takes some practice and careful attention to workspace setup. I've never done MIG, but I imagine it's a bit less of an issue since you aren't constantly trying to get the electrode as close as possible without ever touching. I could see this product being pretty good at telling students "hey, you're holding the torch at the wrong angle" or "you're going to fast" or whatever. Basically, teaching students a few good habits from the beginning.