The generally accepted assumption is that the LARGER you are as a rider the LONGER, WIDER and more volume you need. After yesterday, I am no longer a believer. I mean, that assumption is certainly true, but isn't the only answer.
I built a board, the painting is detailed here, the shape and construction isn't: http://www.wakeworld.com/MB/Discus/messages/87668/727367.html?1252205289
The board is 4'5" long and Dennis is in the 280 pound area. Tribal knowledge would dictate a response of you'll never ride that - a minimum of waht? 5'3"?
I took this video of Dennis, so it's not great quality, but it should give a good indication of Dennis actually riding it - the lipslide is demonstrative of that: http://www.youtube.com/watch?v=e_pWkQzBdnY
These pictures don't do the riding justice, but I live the hang five
Dennis is 6'2" or so inches tall, so hanging 5 is merely moving his front foot forward.