cblake,
You forgot one other problem "skeptics" have with the idea of break-in:
Speakers vibrate, tens of thousands of times a second, in the case of tweeters. They have only a couple of moving parts and they're made from materials with properties of deformation that are very well known. To that last point, do a bit of research into how much titanium, a common material in tweeters, has to be displaced before it assumes a new structural form. There isn't a speaker on the planet that distors the tweeter to that degree (I've posted it before on Axiom).
But more importantly, it is fallacy to believe something simply because people say so. Were I to base my world view on the same rationality common among audiophiles, I'd still be a religious man. You must provide me with evidence before I accept something to be true, especially something that is counter-intuitive.
