Clearly – a coach could theoretically protest any game, but does the USSF offer any guidelines to leagues regarding what might make a game truly “protestable”?

Or to re-word it – what type of referee errors might be grievous enough to result in a protested match being replayed?

We have differing schools of thought. Some here would say that any misapplication of the law, such as an incorrect restart, would qualify.

Others would pose that the error must directly impact the outcome of the game, for example, not allowing a goal scored from a corner would be a referee misapplication of the Law which directly impacts the outcome. Whereas, awarding a corner kick when it should have been a throw-in, and then the corner results in a goal, would be an indirect impact. The players had the opportunity to mediate that misapplication of the Law.

Of course, leagues prefer not to incur the expense of replaying any games at all. That financial concern aside – are there any guidelines for how a coach or league Board might determine if a protest is worthy on the basis of the referee’s performance alone?

USSF answer (October 24, 2011):
There are no national standards for protesting the result of the game and the acts of the referee. Traditionally there is only one reason to protest the decision of the referee, and that is solely for a decision that is counter to the Laws of the Game. In other words, a situation where misapplying the Laws does indeed affect the game or where a referee clearly sets aside one of the Laws of the Game.. There can be no protest on a matter of referee judgment.

Equally traditionally, many protest committees pay no attention to the facts of the case, no matter how rationally reasoned and presented.