> I’m about to re deck my Osprey double. I want the new cockpits closer
> together than Pygmy’s original plans. (At risk of valuing style over
> substance, my wife and I are always in “sync” and prefer being close
> enough to touch... even when we’re paddling)

Uh huh. "come here so I can whack you with my paddle" eh? :-)

> I’d like to know how the placement of the cockpits (center of buoyancy?)
> will affect the boat’s behaviour in beam winds. Apparently designers build
> boats to turn into the wind slightly rather than downwind. Since the bows
> of kayaks are invariably higher than the sterns and sea kayaks have so
> little rocker, it seems the bow would catch more wind and turn downwind if
> the paddler was positioned in the center. I can’t seem to find any source
> that describes the effect and how to control it. Apparently everybody
> talks about “Weathercocking”, but nobody ever does anything about it.
> (pardon the paraphrasing.)

There's more to it. Hull shape plays some to. But as a general statement, the further aft you place the center of mass, and the further forward you place the center of effort (from weather), the worse the boat cocks to leehelm. Which is why sailboats don't place their mast up at the bow, usually. Reverse it, and you've got weatherhelm. To get fancier, you've also got to consider how the hull is sitting in the water. If you've got a lot of bow hull wet, and only a little stern, this will counter the effects of wind to a fair degree. (Notice how I'm avoiding all numbers and math?)

The other affect to consider, especially when bringing mass in towards the center is the dumbbell effect. Mass at the extremes makes a body slow to move when compared to a body of the same mass with the weight in close. Take a dumbbell of 20 lbs and you can spin it far quicker then a barbell of 20 lbs because the mass is closer to the center, or axis of rotation in geek speak. So scooting in to be cuddly can make your boat squirelier and quicker to cock. Of course, this also means better manueverability.