This is in total agreement to what I have been saying all along, bit by bit. You have put the words in great order and communicated the ideas very nicely. The 3"Ps" and the 4"Rs" can only work with that very much forgotten "common sense". How does all the dissent fit into the game? Can you allow yourself to let the players "vent" and then be done with it? Can you do the same with the bench personel? Can you listen to the comments and grow from them?
We all need to think of these things while on the field.

Sorry I'm replying to this thing a couple of years after it was first posted, but something needs to be done about this...

In any sport, at any level, there seems to be four types of officials. One type lets players, coaches, and fans get away with any type of disagreement. Another cards someone everytime they so much as throw up there arms in the international symbol of "wasn't me". A third hears some disagreement (legitimate or not) in his/her first game and quits. And finally there are those who get it right.

I think that it's very much a personal decision, but there are some relative absolutes. As soon as it changes from a disagreement about a call to a personal attack, stop it right there. Calls are fleeting. You'll never get more that 50% of people involved in a match agreeing with a call. Stand by your call, but don't get personally attached, like you're handing down the Ten Commandments. But as soon as a coach/player/fan pulls out the "you suck, you're the worst ref in the league/country/world/time, you shouldn't be a ref, etc," you have to stop that immediately. As soon as someone drags out any sort of profanity, even very, very, minor profanity, such as G-- D---- or hell, I'ed shut that down pretty quickly. The idea is not to give out as many dissent cards as needed, it's to make sure as few are needed as possible. Try talking to a player. "Another outburst from you and it's a card" will go a long way to shutting up a coach or player.
I said don't get attached to calls/non-calls, and now that I think about it, that really personal. As a general rule, treat personal attack as much worse, but sometimes you really feel strongly about a call, which is ok. Cards are my big thing. Just as I reserve the right to card people for certain offenses based on my judgement, I reserve the right to not card people for certain offenses based on my judgement, and I don't tolerate much demanding of cards. Also, notice the difference between disagree with a call, and whining just to whine. You can normally tell if you blow the whistle in a situation where the call could have gone either way, and before any signal at all, a coach/player/fan is yelling at you. Don't take that, if you're gonna disagree with my call, I'ed appreciate it if you waited to find out what it was before you argue it.

I don't have a theory of dissent to offer, merely my experience. Perhaps it's because I'm in the rural South or perhaps because soccer remains relatively new here, but I don't find dissent in the U-ll - Varsity High School age group to be a serious problem. I work very hard to be in position, and the kids and fans can see that. I try to have a complete knowledge of the LOTG so that I can offer an immediate explanation to the coach/parent/player at half or after the game. Those two elements seem to quell most problems. Otherwise if the dissent is public-- that is, I heard it and at least one other player heard it-- then I pull a card immediately. That's the end of the problem for that game. And often I can't help but laugh a little as I do so-- most dissent is silly and uninformed. I don't take it personally, but I won't let them disrespect the game, so in high school off they go to think about it. The last time that happened, a couple of weeks ago, the player came to me at half and apologized.

I suppose in more soccer-savvy areas and in other regions refs may have to deal with this problem more often.

I don't believe officials in any sport should use ultimatums like "Another outburst from you and it's a card". A comment like "no more, coach" or "that's enough, #20" is the same message without getting you into an absolute you can't avoid. Also, anything that sounds like a threat will create resentment and we don't need any more of that.

judge dissent swiftly and carefully
 

Dissent should not be allowed. However, you must judge each situation carefully under the following three conditions.

1. Does this contribute to my (the referee's) miscontrol of the game.

2. Does this bring the game into disrepute.

3. Was what was said verbally unacceptable and directed at a game official.

If yes to 1 or 3, a caution should be shown for dissent.
If yes to 2, a caution should be shown for unsporting behavior.

Be lenient when possible. Don't let little, harmless comments like "i was going for the ball" or shaking of the head bother you and incline you to caution players for it. Remember, they are emotionally involved in play and will often react disagreeingly even when they know they are wrong.