The mute is there to keep chat clean. For example if I typed SOB out with the actual words in game and only the B part of the phrase people still would get the meaning and if there was a little kid playing Pl, Sl ect on his parents iPod, iPhone, IPad, Android, Chrome ect. And if he/she can read he might start going around saying "Son of a" which just looks bad on the parents part and so on. But there are things that should be muted but are not an there are words that shouldn't. But you can't be perfect.