Wednesday, October 31, 2007

Stay Inside the Opposition


I screwed up.

I said I would write a series of posts explaining the sometimes abstruse sailing writings of Dr Stuart Walker in language that the average sailor might understand. But my first post in this series, Big Fleets and Small Fleets, had a sentence that Litoralis (MIT graduate, former junior sailing champion and college sailor) didn't understand. If he doesn't get it, I guess it may have confused a few others too.

So what was the advice that was so hard to understand? I paraphrased it slightly in my post, so let me quote the original sentence from Chapter 5 of Dr Walker's book, Positioning: The Logic of Sailboat Racing (with the words that caused the confusion in bold). In big fleets, Walker says that
rarely is one side of the course obviously advantaged, nor is the wind oscillating so you can play the shifts. So...

you must continuously play the fleet, "taking what you've got when you've got it." "keeping inside and to windward on the tack out from the rhumb line," "ahead and to leeward on the way back," "avoiding the laylines," "digging back in" whenever the opportunity arises.

Wait. What do all those quotation marks mean? Surely the learned doctor is not guilty of the sin of unnecessary quotations. No. He must be referring back to advice in an earlier chapter. Isn't he?

Well, not exactly. Chapter 3 Strategic Principles sorta kinda addresses these issues but without exactly that language. Chapter 4 Racing Maxims is just a list of bullet points covering all kinds of topics and a couple of the points are close to that quoted paragraph, but not the same words. So what the hell is our friend quoting?

Ahah. Here it is. In Chapter 33. Whaaaat? Walker quotes Chapter 33 in Chapter 5 without telling you? Yup. Now do you understand why his books can be such a hard read?

So what the hell does it mean?

Well, it's all about risk management. Let me just emphasize again that this advice is for those situations when you can't be sure that one side of the course is advantaged, or that you have a reliably oscillating wind. Conditions that my friend Mike, from Mike and Charlie, seems to sail in about 90% of the time.

Walker says stay "inside" on the tack away from the rhumb line, and "ahead" on the way back. What he's saying essentially is that whichever tack you are on, you should aim to be closer to the center of the course, the "rhumb line," than your opposition.

And why is that? Think of it this way. You do know that when you're on the layline, however the wind shifts you're going to lose to other boats? (If not, I'll cover that next week.) So, on the layline if the wind shifts you have a 100% chance of losing out. On the other hand when you are in the center of the course there is a much greater chance that a shift will be to your advantage. Between these two extremes, the probability that a wind shift will favor you is on a spectrum: near the layline bad odds; near the center of the course better odds.

So if you don't know what the wind is going to do, by all means move out to the side of the course early, on the lifted shift and/or towards the side of the course that might be advantaged, but when you get a header dig back in towards the center of the course and try and stay closer to the rhumb line than your opponents. That's the way to play the odds.

Does that make sense?

Here endeth the Second Lesson in Walker's Words of Wisdom on Wednesdays.

1 comment:

Litoralis said...

OK. It makes sense now. At least as long as you stay on one side or the other of the rhumb line.

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