Ok, fellas, I'm getting confused here.
We started talking about control in following seas, then branched off into Autopilot malfunctions (a very good subject), and are also dealing with a related topic (cavitation in quartering seas) on the other web site (C-Dogs).
Maybe we should get Tyboo or Bill to separate the Autopilot discussion from the following seas one for sake of clarity.
Then I have a question after re-reading through the discussion up 'till now:
Are you folks with the autopilots using them in following and quartering seas of any size? If so, I think that something doesn't match up here with what I learned from 30 years of sailboat racing, namely that it was ultra important to steer actively through each wave to make use of the energy in the wave and present the hull to the wave properly to minimize forward resistance and generate maximum forward speed. This puts you in control instead of the wave. You have to make it your friend, not your enemy.
Active steering to promote surfing and to minimize forward resistance to the boat results in steering a weaving pattern as one feels the forces of the waves acting on the hull and steers to slip forward with minimal resistance and maximum speed. This is harder to sense and do in a boat the size of a C--Dory than a light 15-20 foot planning sailboat, but the process is the same. Probably takes longer to learn in a heavy, less sensitive boat.
Make the wave push the boat forward on the wave's front side, surf down and across the wave face, and, when necessary or possible, climb the backside of the next wave ahead at the lowest possible angle and then drop through the lowest point in the crest and start down that wave's front face and begin the process all over again. This usually results in a more or less continuous but variable "S" course pattern, not a straight line.
Another variation here is to try to vary the throttle to stay on the front side of the wave, letting it push or surf you along, trying to stay ahead of the wave's peak behind and avoiding digging the bow into the trough ahead.
With the C-Dory's tendency to get it's butt pushed around by following and quartering seas and the subsequent tendencies to dig in the bow and broach, careful throttle control and placement of the boat in the wave forms becomes of paramount importance. And the last thing you want to do is just play the "paralysis game", letting the wave do what it will with you!
Now I know the C-Dory isn't a surfboard or a sleek narrow displacement hull, but it seems to me if you're using an autopilot to steer an absolute straight course through following or quartering seas, you're "dead sticking" it, rather than delicately piloting the boat through the moving sea of energy waves.
I'm not trying to pick an argument here, but I know it's better to steer through this stuff than to point the boat and hold on.
We used to take the C-Dory out at Half Moon Bay below San Francisco and had to come in around the reef that stick out from Moss
Beach and generates the Mavericks surfing paradise in the winter.
Now we didn't go over the reef with the surfers in the 20-30 footers, but as we began to go down and around the reef, the swells became increasingly gentle as the wave faces spread out, and when they reached a reasonable level where I felt comfortable with it, we'd drive up over a big one and launch down and across the face for a ride. What I knew from small boats had instant application and my instincts were right.
Smaller swells and chop aren't much different, except that it's sometimes very hard to find a discernable pattern to make the steering task easy and one has to rely on the instincts developed in more uniform conditions to sense how to make the best use of the waves and, more importantly under these conditions, find the easiest path forward, much like going forward into confused seas.
I guess I really miss the swells and larger waves we used to experience before moving inland. Sometimes it was pretty scarry, but the adrenaline rush and thrills of staying upright and on the edge made for quite exhilarating rides. Still blowing 40 up in the Sound? Joe.