Is it sensible or stupid to put a swivel between anchor and rode to allow the boat to rotate around the anchor during tide changes, or stupid because its an added complication and weak link?

Bill Balme

Many years ago when I was a bit less informed I used a stainless steel thimble connecting to a heavy duty galvanized shackle. This was completely submerged in salty water, part of a trot mooring system. Towards the end of the Scottish sailing season the thimble was in perfect condition, the shackle was half eaten through. It was replaced with an all galvanized system. Any comments?