Mark Z on canting rigs, from the Fboats discussion:

"Canting became de rigeur for 31 1Ds.

We ran a doubled 3:1 (two lines pulled simultaneously) in Precourt
eyes that were pulled by a 4:1 that was run along the top of the float
(s) to behind the aft beam where the adjustable end turned to a
clutch mounted on the aft surface of the beam close to the inboard
end. I am pretty sure the final (ignoring the massive friction)
mechanical advantage was 12:1.

Ira's posted pics of Rut Row's system are roughly similar to what we
had.

To tack we would ease the rig down to leeward (awkward in every way)
and pull up the soon-to-be windward side. Then tack. We never
pulled the rig to weather while loaded.

Jib cars had to be moved aft (w/rig canted) to compensate for a) the
narrower slot and b) the "less raked" position of the stick while
canted.

The forestay stayed the same length, so canting the rig to either
side would move the hounds in an arc... the farther away from center,
the farther forward the hounds moved (taking the top of the mast even
farther forward). This change dramatically effected the helm, making
it quite neutral compared with the normal weather helm we have/had
with the rig centered.

We worked it hard for two years, and I can't say (sorry all you pun
averse) we ever found the canting system to be worth (in speed or
point or feel) the complexity it added to our little boat with 2 or 3
crew program. Don't get me wrong, the system and the penalty we bore
for it did not cause us to lose an event...it just never proved to be
something that would allow us to win something we couldn't have won
with a centered rig. We did lose on corrected time a race to two
other 25s in St. Joe in light air. We beat them across the line so
had we not had the penalty we would have won that race, but our
problems had to do with being on the wrong side of the beat, NOT our
speed.

We are now back to sailing with (gasp!) STAINLESS SHROUDS with
turnbuckles!!!! We trade weight for (less windage and)lack of creep,
the rig stays centered. And the float top is free from annoyingly
taut amsteel blue dental floss and harken double blocks. The extra 8
meters of line trying to tangle with the main/screacher/spinnaker
sheets is not missed either, nor is the weight (of the two clutches,
4 harken doubles *2 w/becket*, 4 precourt deadeyes, lots & lots of
line, fasteners, etc.).

Like it or not, 3 sec/mile is almost non-existent on a course of a
few miles. On a 300 mile course its a different story. None the
less, we did not suffer from the approximately 15 minute penalty we
carried for the Mac race in the two years we raced with the canting
system. Do I honestly think the canting system improved performance
over the entire course enough to cancel-out the rating penalty?

No.

Mark Z
crew on Gamera, 2000 to present"