Novel Mobile-specific Content Handling

On my current project I was tasked with creating an iPhone-specific view with the constraint that it had to be the same page as the already-constructed desktop-optimized version and the requirement that content be moved in the new mobile view. For whatever reasons I’ve had rather mixed results device-sniffing with javascript in the past but almost universal success using media queries in CSS to target difference devices (and I was already doing so on this page). So I devised this scheme for determining if the viewing target was a mobile device and then moving the desired content appropriately. I haven’t yet figured out if it is clever or full of hidden perils. If you have an opinion give me a shout. It works and the only drawback I see so far is it requires an extra empty div on the page.