Hehe, that is a clever/amusing idea. But even if it's true that this constitutes a meaningful signal (there are plenty of ways to get friends that do not involve intelligence, kindness, or effectiveness that leave no visual cues - like extroversion), it's a signal so subtle that I don't think I would pick up on it.
Edit: It would work for simpler things though - we wouldn't be as impressed with David's intelligence if his muscles were as large as Goliath's.
I would have counted extroversion as in the same reference class as intelligence, happiness, kindness and effectiveness.
This is a repository for major, life-altering mistakes that you or others have made. Detailed accounts of specific mistakes are welcome, and so are mentions of general classes of mistakes that people often make. If similar repositories already exist (inside or outside of LW), links are greatly appreciated.
The purpose of this repository is to collect information about serious misjudgements and mistakes in order to help people avoid similar mistakes. (I am posting this repository because I'm trying to conduct a premortem on my life and figure out what catastrophic risks may screw me over in the near or far future.)