u-chappy, I think you'll find that you repeated what I said (albeit with more technical info!), ie it is not necessarily that the adverts are actually louder, it's just that our perception of them is louder. There are already rules in place about adverts, and the fiddling with the levels is a way for the advertisers to get around the rules.
As for "they must be doing it on purpose" - unless you're being ironic, of course they are. Don't forget that adverts and the associated "industry" around them are made by people who spend more money on a meal out than most of us spend on our family's food for a month. They're rich, they're powerful, and there's little chance that Joe Public's intense dislike of their underhand tricks is going to stop them becoming even wealthier. I dare say that they can even find "proof" that people LIKE having the adverts sound louder. (I know that Sky claim that they get requests for the end credits of programs to be squished/talked over as apparently people are incapable/too bone idle to use their remote/paper/TV mag/computer to work out what is on next).
Until there is a complete change in the way we watch our media, we are (unfortunately) stuck with the ads, and I can't see the industry dropping the perceived volume without another way to try to sell its wares. Mind you, there does seem to be an increasing use of product placement (cf. 24 Season 4 where - just in case we missed a lingering close-up of the Cisco security software preventing a terrorist intrusion - a character informed us that it was OK, the CISCO SECURITY SYSTEM had stopped the hack *rolls eyes*).
Anyway, I take it that no-one has used a VolumeMaster? (The product seems to be discontinued, so either it was a bit poor or it worked too well!)