Figment wrote:I'll hazard a guess that lowering the board that far (moving the CLR forward) will induce a lot of weather helm.
I doubt it, I think that would be a pretty serious design error.
Centreboard boats are designed and balanced to be sailed with the board down,
on the points of sail where it helps, i.e. on the wind.
Raising the board to reduce lateral resistance allows leeway,
so it's a pretty sloppy way to reduce weather helm, by skidding through the water!
On most boats, too much weather helm means they are overpowered.
The answer is therefore better sail trim (i.e. flatter sails, take a reef, etc.),
not reduced lateral resistance.
If the board is not supposed to go down all the way to vertical, it will be designed that way in the first place, e.g.
This drawing is of a Paceship Westwind 24, by Ted Hood.
When I sailed this boat, my rule of thumb was board down on the wind,
board up off the wind, and down about 1/3 on a broad reach.
The hull was very rounded and slippery,
so it was easy to feel when it needed the board to keep going straight.