Why not ask CPW/TalkTalk for THEIR version of the Webwise system diagram - the one on Wikipedia
http://en.wikipedia.org/wiki/File:Phorm_cookie_diagr...
or the one on the BT Webwise site
http://webwise.bt.com/webwise/customer_choice.html
It would be in their interests to publish their system which avoids the non opted in customer going anywhere near Phorm supplied, Phorm programmed DPI kit. And to do so with a diagram of their own system.
Also ask them HOW they distinguish between their customers who are in the system and those who aren't. By means of cookies? By means of browser hijack? Or by a network based system based on fixed IP address or address ranges? If they are genuinely trying to provide a proper ISP customer opt-in, then they will tell you the details. If they are trying to fudge the issue, with weasel words, you will get a vague answer and no diagram.
If they fudge or waffle or dissemble (or talk vaguely about the customer who has not opted in "not going through Phorm's system") then they are trying to pull the wool over your eyes. And believe me - the ISPs are very good at that and have been doing it for well over a year, and in BTs case for over three years.
It IS possible for the ISP to provide a genuine no-interception opt-in, (for their own customers) but they have to make it very clear how they do it - there is so much wriggle room and weasel wording used in this argument, you have to really check what they are saying on the record. Phrases like "Phorm's equipment" are just a way of avoiding the question - because the DPI snooping kit that your traffic goes through in their network, is NOT Phorm's equipment, it is merely supplied and programmed and updated and probably maintained by Phorm, but it "belongs" to and is "operated" by the ISP at least in theory. That's the wriggle room and the weasel wording.
You might also ask them how their TalkTalk system avoids abusing website copyright, and forging cookies, and abusing website trademarks.
It can't.
You might ask them if their system can detect and respect private Facebook "Friends" pages. It can't.
You might ask them if their system will avoid the accusation of diversion of trade by exploiting website databases to serve the websites visitors with ads for their competitors products. It can't.
Don't let TalkTalk sit on the sidelines and pretend to be whiter than BT or Virgin Media. Make them prove it, absolutely clearly. And if they won't, if they insist on being coy, on witholding details, then assume that they are simply pulling the wool over your eyes, hedging their bets and simply looking to attract customers who are leaving BT or VM.
It is not possible to use Phorm's system and maintain with a straight face that you are respecting privacy or copyright or database law or data protection legislation. But I have no doubt the ISPs will try it. And TalkTalk are trying that now. Let them produce the evidence to back up these claims or just line up with BT and VM as one of the villains of the piece.
Come on ISPs - its time to talk turkey and stop hiding behind Phorm and Mr Ertugrul. It's YOUR time to answer some awkward questions. YOU are in the firing line now - its your DPI kit, you operate it, so tell us how it works!