RE: Heavyweights Waveboard
Floyd. Yes, in an absolute standstill, how far you sink (or how "high" you float) is a matter of the volume to total weight ration only. But my point is that when it comes to sailing the thing, volume is only one part of the equation and a pretty small one too. Even far, far below the planing threshold, dynamic effects of the surface area of the board will help it not sink. And for planing sailing the volume does not matter much at all (other than as a general guide for board _size_).
That wave boards are small depends on that it is simply difficult to put in a lot of volume in a board and keep it performing on a wave. So, wave sailors simply learn how to handle small boards. Slalom boards could be pretty small, people that ride the iS50 speed often testifies it works in surprisingly low wind speeds if you just ensure you never loose planing. But for practical slalom sailing you will loose planing now and then and then some reserve volume will help you accelerate from faster which is crucial. It is especially helpful when you are carrying a big and heavy sail (like a cammed 8.0 sail).
But it is an interesting question wether one given sailor could choose all his boards in similar sizes with just different designs. I talked to Jason Polakow a while ago. He said "all my boards are between 73 and 76 liters". Same with Levi Siver. Not much variation. That goes for quite a few of the wave sailing pros that use custom boards. It is more difficult to do with production stuff but i recently sold my Acid 74 to a guy already owning a EVO 74 and he is super happy with his quiver and the two boards fills different roles for him. The pros that are on production boards tend to use a much wider span of sizes (like 75-85-95 or 70-80-90 for an 85kg sailor) and its very much a matter of taste and style how big boards they use on a given set of conditions.
In practice most of us tends to want some extra volume in our light wind boards though and using the "Polakov model" would probably not be the best thing for most of us.
But when everything is said and done, what matter is what a given board is designed to do. You could probably build a super light wind slalom board for a light weight sailor around 70-80 liters, but with the available designs, even a light weight is likely to be more effective on the iS101. That is what I also meant with my comment on the new EVO. For a performance wave boards, there is a lot of volume in there but maybe more importantly is that many other design elements of the board has been adjusted to fit the criteria which is "an effective performance wave board for heavier sailors" (ie not _primiarily_ a super floater for semi-heavy guys).