Sorry, I'm kind of a "by the book" guy. If I'm going to break some rules, I at least want to be aware of it! [&:]

Here's the score:
FAA:voluntary compliance only. Not a law. You can fly high if you don't cause any trouble.
AMA Insurance (partner company): Does not have the rule. You will not be denied insurance (to the best I can tell, I'm not a lawyer).
AMA Safety Code: Black & white, don't fly over 400 feet. As I said, this is AMA's way of voluntarily complying with the FAA policy (as a sign of good faith).

There may be provisions to exceed the restriction for events or at specific sites, but the method of doing this is not listed in the Safety Code for 2006. As it stands, if you fly at a chartered club, then you are expected to follow the Safety Code. However, that doesn't mean that some clubs aren't turning a blind eye in some cases. But, if such "ignorance" activity causes an incident with a full-scale aircraft, then it will probably END any negotiations for increased altitude with the FAA.

All of this is new and some changes in both directions are to be expected. The point is that AMA wants to work WITH the FAA, not against it. FAA carries a lot more force. I can guess how this came out. FAA is under pressure to reduce future terrorist activity, and UAVs is certainly a potential tool for such things. FAA puts forth to AMA that models are to stay under 400ft. At the time, AMA was probably given the choice to either comply, or watch it get pushed to become law. With the anti-terrorism drive still going strong, this would be an easy thing for FAA to do. While AMA adheres to the policy, it can continue to negotiate for increased altitude, since policies can be easily changed.

My point is this: AMA has to work within the space that the FAA grants us. If we start copping an attitude and disregard any voluntary compliance, then FAA will simply clamp down and make the compliance nonvoluntary. The FAA will not listen to our requests if we earn a history of being difficult to work with.

Of course, there is the option of doing away with AMA and having FAA take over all RC activity, but I doubt FAA has our best interests in mind.