I used to work with a guy who could stand on the ground, look 20 feet up at some crazy offset+turn, then bend it, we would take it up and it would fit like a glove. I have just never been that good. I can get close but I'll usually need at least one tweak or two (sometimes I just throw the thing away in disgust...like when I bend it backwards!).
I don't know how much grilling I could take as an expert bender could probably trap me into saying something stupid. For that matter, I say stupid stuff all the time without being trapped.
As for a quiz: I remember talking to a builder in Atlanta who built multi-story buildings. He said he interviewed a guy one time and started giving him the "competency test". He asked the guy if he had his own plumb bob. The guy said "of course" and showed him a nice new one. He then asked the guy when it was last calibrated...."um, I'm not sure but I can have it checked". That was the end of the interview. The builder laughed and told me he just uses a brick and string!