I thought about this when I read the expression in another thread, "someone was stumbled", they would never tell you who the person was, and simply used it to control you, or it got worse, some times it was "you MIGHT stumble someone" .
Who were these Stumbling Loons of which they spoke ? Not only was it a Control Mechanism, it encouraged you to not be your real self, ever.
I liked the response of one of my JW relatives to this, where they expected him to change the person he was, he said "These people accusing me are not perfect are they ? No, well then, they cannot expect perfection from me". Lovely response.