treblig,
I have not heard of 'the test' but I have been taught a similar thing.
My uncle Ron used to hang a white cotton bedsheet up at the side of a path on his farm.
He taught me to take a shot at a black cross marked on it every day as I walked past it on my way to the rabbit warren.
Eventually I blew a hole through it, that showed where my point of aim was in relation to the cross.
When he refused to bend my stock it also showed how adaptable the human body can be.