Re: Proof
Take a look at the report: Glasnost approach would detect the presence of such differential treatment, but where on the supply chain is the issue?
There never (rarely) is a single "domain of control" that is responsible for the delivery to you - and that's Ofcom's issue, if you can't isolate you can't enforce.
In the US it is slightly clearer (and remember this is where the stuff started) but even there there are other issues of responsibility, in the UK our digital supply chain is much more involved.
Disclosure: I was one of the report's authors.
