It was about jibing downwind. Here's a rather technical article describing the sail
design for IACC boats.

"While it is impossible to sail directly upwind, it is possible to sail directly
downwind but as shown in Fig. 3, with true wind speeds such as 5 m/s,
the optimum VMG occurs with a true wind angle of 150 degrees."

http://mapp1.de.unifi.it/persone/All...chards2001.pdf

BTW, its either jibe or gybe, not jybe. That's about as silly as saying "ded reckoning."

"Simple Simon" wrote in message
news
It wasn't all about jybing downwind.


"Jeff Morris" jeffmo@NoSpam-sv-lokiDOTcom wrote in message
...
"Simple Simon" wrote in message
...

Show me an America's cup where on a dead downwind leg boats are
jybing downwind and coming out ahead and I might give a little credence
to your nonsense. The races I've watched show these cutting edge vessels
running straight downwind and only turning slightly now and then to
keep boats upwind of them from blocking their wind.


This has got to be the dumbest thing you've said in, well, at least a few days.

Perhaps you will recall that they showed the downwind "laylines" - what do you think
that
was about?