I switched from a 36' monohull
to a 35' cat about 18 months ago. The monohull
would tack back and forth at anchor when the wind
piped up. This was somewhat uncomfortable but when it stays on one tack I knew the anchor was dragging.
With a bridle
the cat stays almost dead down wind
, even with the anchor dragging.
I don't have any measurements but it seems that the monohull tacking back and forth puts more strain on the anchor. It sure puts a strain on my nerves. The cat has more surface area exposed to the wind but it is in more streamlined shapes, not one big hull. And it stays aligned with the wind.