My (very limited!) understanding of what seems to be coming out of the latest CFD work is that pole masts are not nearly as bad for performance as more traditional theory, like the Catamaran book above, suggested, and that the margin between them and more sophisticated sections really isn't that great. Empirically I guess sailors knew this (subconsciously anyway) in that supposedly superior sections like Proctor Betas and Kappas and things never actually seemed significantly better than round tubes on the water, and those of us who played with wing masts never found ourselves rocketing to the front on a magic carpet either.
I'm also convinced that no-one apart from Bethwaite has really done the raw research adequately, and too many experiments on dinghies have been the pear shape fat end forward section that Bethwaite reckoned was rubbish. We should remember that those lasted on C Class Cats for about 18 months before being replaced by superior technology, so there is a second opinion on his evaluation. Bethwaite's sticks did seem to work, but they couldn't be mass produced and were barking heavy.
Inadequate theory gets folk into a lot of trouble - another one you'll see coming up on the Internet forums is of folks who gain the big idea that a mast in fromt of a sail is trouble, so they design rigs with the mast at the back, or off to one side, or a bipod or something and rig a boat with just a big jib. Naturally the result is always rubbish! That gets a good rating in the book too doesn't it. Still I should talk, I've made enough mistakes with inadequate theory I didn't understand properly in my time:-)
I still reckon there's unfinished business in wingmasts, although I'm less enthused than I was 5 years ago but the trouble is you probably need to devote two or three seasons of going slowly and buying new masts and sails every few months and recutting sails every few weeks. You've not only got to solve the basics of getting a solution that is aerodynamically superior in a wide range of conditions, but also work out a way getting enough gust response into the mast, and probably work out how to get twist into the mast as well. Then its got to be light and yet strong enough to cope with poor handling on and off the water. Short of Larry Ellison saying ******* this Americas Cup nonsense, I want to build a team to win a Cherub World Championships, I don't really know who could devote that much energy and resources... I guess as good a demonstration of my current opinion on these things is that although my Canoe would be allowed a wing mast I'm not looking at getting one, instead I'm concentrating on gluing bits on tubes for improved bend characterstics and gust response.