A fair point, Steptoe, but I wouldn't consider myself an internet 'expert', no would many people who have any sort of experience! The whole point of a forum is to share experience - individuals can make up their own mind what advice to follow (a bit like when you're about to have children for the first time....)
There are clearly many different factors that will affect pad and disc life and braking performance. In terms of pads and discs, I can only think that the effective life of either comes from the nature of their application and use. I've run EBC's for years and have never replaced a set of discs on any bike - I did 20k miles on my last Fireblade with no problems on EBC pads, with fairly heavy (road) use the discs were fine, nor, in Japanese bike circles, have I come across EBC pads being notorious for chewing up discs (at least not over my last 20 years of motorcycling). It could be that some manufacturers discs are softer than others, and I just haven't come across this yet (my GS is my first non-Jap bike, ever!)
I understand the philosophy that if you have a harder pad then something has to give to be able to get the friction to stop. However, the overwhelming impression I was given was that those who run harder pads see longer life out of their discs. If there was a magic combination of pad material and disc alloy which gave incredible stopping power coupled with massive longevity, i'm sure we'd have come across it by now. As it is, something has to be sacrificed - the pads or discs eventually wear out. As I said, i've used EBC's for years, replaced tens of pairs on umpteen bikes and have never had to replace discs.
I would go with the argument that softer pads create greater friction, which in turn creates more heat and the risk of warping a disc with heavy use, but that's different to wearing them out. Again, i'm not an expert, but it's a theory i'd easily accept.