Internet Watch Foundation in the news again

The Register reports that the UK ISP Demon has removed access to a larcge chunk of internet history.  The error pages that users are presented with apparently imply this is in response to the site being listed on the IWF blacklist.  Amusingly, El Reg reports:

One Demon customer tells us he was unable to visit archived versions of websites run by the BBC, Parliament, the United Nations, the Internet Watch Foundation, Demon Internet, and Thus. In other words, this customer points out, Thus is blocking its own web history. "It is nuts," he says.

This does seem to be using a sledgehammer to crack a nut.  I presume there are dubious sites archived at the wayback machine, but to block the lot seems a bit extreme.  Presumably the internet block derives from the way Demon have sought to implement the IWF blacklist.