On my last C30 I noticed that when anchored in high winds she would start sailing at anchor and begin tacking back and forth. Outside of just the discomfort, there is concern for chaffing and excessive wear. Have others experienced this and/or do you have any remedies to prevent/mitigate the condition?
Yes. Posted an article awhile ago about my experience dealing with chafe and/or excessive wear tied to a mooring in a blow. That article here:
Departed Shelter Bay Marina last Saturday, February 18 to spend several days on the water, weather permitting. Actually the day started out pretty nice; reasonable temperature, some sun breaks, but wind on the nose what little there was. First stop was Eagle Harbor to spend the night. Quiet night tied to a mooring ball with a single 5/8th inch three strand nylon line.
Sunday morning awoke to a strong easterly, which blew into the harbor a long fetch of rolling chop. Belle-Vie rocked and rolled all day, swaying back and forth, to and fro. Over the years I've made a practice of establishing land marks whether at anchor or on a mooring. I check those landmarks periodically depending upon sea state, as well as moorings and anchor set. I also make it a practice to back down on a mooring just to make sure that it will hold.
Two hours earlier I had checked the mooring line and it appeared fine, but in a two hour time frame the mooring ring cut through the line. I was below deck in the aft cabin just finishing an article when I glanced up to check my landmark and it was not there. Dashing up on deck found Belle-Vie adrift heading for the head of the harbor's shallow waters a short distance away, I light off the engine and bring the boat back into safe water. Whew! That was a close call.
The wind was still blowing hard and lots of heavy chop a I tried to snag the mooring. My final try that worked was to secure the eye of my long dock line to the midship cleat, approach the mooring as if approaching a dock, got the line through the ring and secured it to the bow cleat in the nick of time. Then I worked the ring forward to the bow where I was able to secure a new mooring line, then released the midship line. This time I doubled up the mooring line leaving the backup line a bit slack and the primary carrying the load.
The reason the mooring ring cut through the line was due to the old way that I used, which was to secure the eye to the port cleat and the bitter end through the ring and tied off on the starboard cleat. When the blow caused the boat to yaw, the line was sawing back and forth through the ring eventually chafing through.
So I've begun using a new mooring technique offered by Michael Davis, which is shown here in these photos. Makes more sense and would appear to minimize/eliminate abrasion caused from the boat yawing in a blow.
Michael was given this tip from a cruising instructor, which loops both ends of the line back to the same cleat as opposed to the way I, and most others do it, eye on one side, bitter end on the other. I did it this way because the cleat provided insufficient room for a cleat knot on the same cleat as the eye.
This new arrangement will need a blow test for sure. A winter cruise report in the offing.
This is the only way it should be done. I’ve seen others do it in a way that allows the sawing action as the boat swings, and offered unwelcome advise. 
