The second way (opening the image itself) is probably quicker because the browser only has to open a single connection. If it receives a location directive, then it has to send another request to the site. Further, I doubt that the "single-line effect" of <PIZZA> is much of an issue - even a large gif would get parsed so fast it would be hard to measure, and I doubt the webserver would be able to send it faster.

P.S. Thanks, merlyn, you are right about the obtuseness. I'd change the original post but then your response wouldn't make much sense. :)