The B-M-T definitions seem to work OK for DiMarzio and Seymour Duncan though, and you kinda know what you're getting?
Sort of.... but isn't that largely based on you, the customer, knowing a couple of the pickups from personal experience, then using that knowledge
plus the tone charts to make new choices? I don't think anybody's tone charts really work as stand-alone tools. And (unless I'm missing something here) I don't think DiMarzio and Duncan's numbers give much indication of relative performance and output, any more than the BKP ones do. They're still just giving an indication of the EQ for that particular pickup.
(Incidentally, for the models I've tried, the numbers in the DiMarzio tone charts always seem about right to me, but the Duncan ones seem way off. I guess it depends what they're taking as the "average" or start point.)
Gotta say, I'm a bit baffled by this thread. OK, so the clips and tone charts don't work for everyone. But loads of people were asking for them, for
years. Now we've got them, and suddenly we're piping up with the "what guitar was it, what amp was it, how was it recorded, apples and oranges..." stuff again. Surely we've been through all that enough times? If they don't work for you, you don't have to use them. We managed without them before! :P