"Once the nets cast it will just keep on cathing the smaller and smaller tiddlers."
A fish is a fish is a fish. However, I suspect it is more likely to start drowning dolphins than catching small scale file sharers.
Look at it this way: if the ISPs / governments / IP groups can identify file sharing then why aren't they going to court asking for money a lot more than they do now?
So at the moment you have file sharing figures based on a few assumptions, such as the figures plucked out of the air by the record companies and the assumption that most, if not all P2P and large file downloads are illegal.
Now, we all know that piracy is rife, it always has been, just back in my day we would need magnetic tapes and a bit of effort to copy albums / computer games / record songs off the radio whereas now it is just a case of point and click and you may as well download as much as you can even if you aren't really interested in most of it.
But that doesn't mean that piracy is as big a problem as the or government tell us it is - to be brutally honest both those groups have serious ulterior motives for controlling and taxing the interweb and very few morals between them.
So, the article states: "If these do not reduce copyright infringement by 70 per cent in a year"
But how will they know? It is not like fake Gucci bags where they can count the fakes and see the levels of counterfeit, or shoplifting where you can see discrepancies in stock accounted for - If only 100,000 people buy Lady GaGa's latest musical offering, is that because the rest of the 7 billion people in the world didn't like it, or because they are protesting against her record company's stance on the web or because they pirated it?
How can you say piracy is down, unless you can absolutely tell who is pirating what, and in that case you don't need to bother with letters and threats, you just go to court and get your money.
All you can tell is is sales are up, but there are a lot of factors that affect sales (quality of product, not pissing off your customers by calling them thieves and cutting their interweb), not to mention the small likelihood that every act of piracy is a lost sale - which it clearly isn't, the reformed pirate may not have the money to buy or they may not want whatever it is enough to actually pay for it anyway.