Thanks, that document looks very impressive and will now sit at the top of my reading list :) Oddly following that link gives me a 404 ('The requested URL /~dy

Thanks, that document looks very impressive and will now sit at the top of my reading list :) Oddly following that link gives me a 404 ('The requested URL /~dyb/papers/3imp.pdf‎ was not found on this server.', seems there is a trailing character '%E2%80%8E'). I was able to find it on google and open it, yielding the link http://www.cs.indiana.edu/~dyb/papers/3imp.pdf http://www.cs.indiana.edu/~dyb/papers/3imp.pdf