How tight is too tight?

[bobbyi]

Correlation is not the same as causation. If the tight players in your sample suddenly started to play more hands, their win rates probably would not go up. The fact they are overly tight is a side effect of their poor understanding of poker. That same poor undertanding causes them to lose money. The tightness itself does not. Essentially no one loses at holdem as a result of playing too few hands.