I'd imagine the "big guys" have bigger problems to worry about than breaking in speakers. Like: It makes no sense to haul amps or cabs (with those carefully broken in speakers) all around the globe so how to dial in some random amp provided in the backline and still achieve your signature tone. By the way, if it's so significant, why don't the speaker manufacturers break in speakers at the factory as a part of the whole manufacturing process? Also, if I think the tone begins to suck after break in period, could I get my money back? If not, then why?