On the A-sail v. S-sail controversy, I have been sailing on a boat with both in the inventory. Over the years, we have used the S-sails only once or twice, mostly because the A-sails just plain work better, especially in the lighter wind common here. I think that is because the longer luff and...
As has been noted, the blooper was invented to provide additional DW sail area in the early days of IOR, largely because the early versions of the IOR rule imposed a heavy penalty on mainsail area, and much less on headsail area. This led to the short boom/ high aspect mains & mammoth...