DIRT
The most important factor in determining a player's GRIT is his uniform. A player who is "containing, covered with, or resembling grit" will show visible signs of his grittiness on his uniform. Dirty uniforms are good; bloody uniforms are better. A true team player, the gritty player is prepared to sacrifice his body at all costs. This is one of the few ways gritty players are efficient, since they probably aren’t as well compensated as their genuinely talented teammates.
Go read it. You will be an infinitely better person for it.
