i dont know loads about this sort of stuff, but isnt what that persons doing exactly the same as every proxy site out there does ?
When someone visits your site from a proxy, often your page gets indexed at the proxy site (although im sure google knows that proxys do this)
Is this the same as what happened with Dom’s site – or is it something different ?
Here is an example of a proxy’s indexed pages….. http://www.google.co.uk/search?hl=en&rls=GGLJ%2CGGLJ%3A2006-34%2CGGLJ%3Aen-GB&q=site%3Ahttp%3A%2F%2Fwww.webthese.com%2F&meta=
can this hurt ppls rankings ?