OK, I should have said "using only logic, I might conclude that it won't work at all". The point I was trying to make was that the poster I quoted was not answering the OP's question, he was just making an unhelpful comment.
If you really want 1080p from the iphone to your hdtv you can buy a cable from apple that will let you display 1080p on your screen... Even mirroring at 1080p!