A couple of questions about handicap and rating

As you say, it’s a thought experiment that takes “measure of quality of rating system is ability to predict game outcomes” to its logical extreme to show that is a poor metric to be the sole one to measure. Not claiming you were a proponent of that, and like you say matchmaking is another very important one, but the whole analysis we were talking about of overall vs specific ranks was measured against game outcome prediction. Perhaps a better, though much harder, metric would be “player happiness that they were paired with people of similar strength” (e.g. not like this guy Impossible to detect sandbaggers/lower ranked people). The whole idea of a person having a rank is based on some averaging, and we need to find the sweet spot.