Whilst in theory users have an option to 'opt out' in practice most users are unaware of this and the process varies considerably depending on ISP. Do you have

Whilst in theory users have an option to 'opt out' in practice most users are unaware of this and the process varies considerably depending on ISP. Do you have any robust data you could share about that? I'd be interested to see it. The only reports I've seen were informal/anecdotal, but if anything they suggested the reverse usually happens, with not many customers opting into filter programmes and those who were signed up automatically generating a fair number of hostile calls to ISP customer support people about wanting to opt out (and quite a few of those in connection with sites being blocked inappropriately).