Not a problem for me, but it’s one of those things that I can tell by the way it feels that not everyone can do it. I don’t know if there really is such a thing as “double jointed”, but that’s what everyone used to call it when I was a kid. I can for example bend just the first knuckle (just below my fingernail) on my middle and ring fingers, locking the middle knuckle, so that I could actually press on the inside of the middle knuckle and it kind of “pops” in and out of place (by that I don’t mean it makes a noise…think more like an adjustable vice grip wrench where you can move it to the right width then lock it, and you have to kind of press upwards to unlock it…kind of hard to describe, but if you can do it, you know what I mean). If you could do that you were double jointed, if not, you weren’t. The other thing would be that I can pull my thumb down so that it touches my forearm…it doesn’t feel great, but it doesn’t cause any lasting or severe pain for me, but I showed a friend who wasn’t double jointed when I was in high school, he tried it, couldn’t do it, forced it, I heard a snap, and his thumb hurt for 3 weeks. I’m betting he couldn’t do the table thing either.