Ok, I've got another theory, perhaps is the proliferation of 'bass boost' on home and car systems that's made the average mix require far less bottom end for the same end result...?

Club mixes for radio you'll notice tend to have less bottom than some of the more banging stuff for clubs ... if you go to a night where they play a lot of commerical stuff a lot of it is hopeless inadequate at the bottom end compared to the more underground club orientated stuff.

Well, that's my theory for the day anyway,

laters, Baz.