Are extremists on an issue a required component?

[Easy E]

The arguments for and against RMGP, on RGP, had me thinking about a topic that I've thought about (in different arenas) before
(NOTE for the uninitiated- the RGP discussed centers around starting a moderated Rec.Gambling.Poker newsgroup).

The topic? Doesn't any good debate REQUIRE crazy extremists, on both sides, in order to more fully expose the issues and develop their solutions?

Or, put another way, no matter how crazy, uncivil, obnoxious, erratic some fringes of any debate are..... would the discussion not be as well defined WITHOUT them? No matter HOW much you'd like to throttle them (or how much they DESERVE to be throttled)?

I've been meaning to put together an essay on this, and hopefully when I have more time, I will (and can add it to this thread) in order to explain my thoughts in detail... but I thought the timing was more important than the final product....

Fire away!