An interesting interview here: From : http://sailblast.blogspot.com/2011/10/observations-from-guys-changing-34th.html
How do penalties do work?
Stan Honey, Director of Technology for the 34th America’s Cup (AC34): Once a penalty has been assigned, whether it’s a limit penalty or whether its S-P tack penalty, the computer assigns a penalty line which is two boat lengths behind your boat and that penalty line is moving at ¾ the theoretical speed of your boat and you have to slow down until that penalty line overtakes you. The reason that penalty line is moving at ¾ of your speed is to give you an incentive to pay it off quickly. The idea is to keep you in the race so if a penalty hurts you, you’re still in the hunt, which keeps the race exciting and interesting. Plus, to have these boats do circles if it’s windy is just too frightening!
John Craig, Principal Race Officer (PRO) for AC34 : It’s taken the teams a long time to get used to the penalty system incurred by the new electronic boundaries. “They would, say, it’s saying 80 meters then two seconds later I was done,” - yeah, you were doing 30 knots! It’s been a process and I’m happy to report there are very few limit penalties anymore. We really are able to keep the guys in the box.
(…)
But what’s the most interesting thing about this whole project is what happens in the morning just after the skippers’ meeting (as an example of how the data is used). Mike Martin (Director Umpiring and Rules Administration for AC34) replays the previous day’s penalties on a screen and all the teams talk about them. What’s fascinating is it’s completely non-confrontational because there’s never an argument about the facts - the discussion is about the rules. Someone puts their hand up and says, “Yeah, I own it,” and in some cases it’s the umpire who’ll say, “Yeah, I called that wrong.” It’s fascinating how friendly everything is and there’s never a dispute about the facts.
What info do the competitor’s have?
SH: The competitors don’t get anything during the race. The idea is to keep the competitors in the same test of skill that we all are at - they have to judge when they’re in the 3-boat length circle, they have to judge the starting line, when they do or don’t have an overlap etc. And they know whatever they do, whether they get it right or wrong, the umpires are going to make the right call so it’s a better test of skill. That was Russell’s vision and he’s been batting very high on those kinds of decisions.
How does this all scale up as far as the 72s go?
JC: That’s the million dollar - the multi million dollar question (LOL) - the 72s - take 3 of the 45s and stack ‘em beam to beam and that’s a 72, then take 4 of the mainsails from the 45 and that’s a 72 mainsail. There’re a lot of people spending a lot of time in design rooms right now trying to figure it out.