## Sunday, June 19, 2011

### Margin of Safety

"Margin of safety, the three most important words in investing."
Those are the words of Warren Buffett, the most successful investor in history.  Buffett became the richest man in the world by compounding an initial investment of $100 in the Buffett Partnerships to a fortune exceeding$50 billion.

"I've had people hand me more major championships than I've won."

Those are the words of Jack Nicklaus, winner of eighteen professional major golf championships, most in history.

So how do we play tennis with a margin of safety so that people will hand us matches, and maybe even major championships?

Let's "invert, always invert" in the words of the great mathematician Carl Jacobi.  How do we play low margin of safety tennis?

Well, to play low margin of safety tennis, we should aim close to the boundaries, that means hit low, deep, and to the sides.  That way we bring the net (low), the baseline (deep), and the sidelines (sides) into play.  All three of the places our shots can miss are in play.

What else?  Well, we should definitely hit hard.  Our acceptance windows get exponentially smaller the harder we hit, so high pace is key to low margin of safety tennis.

How about spin?  Well, we should avoid topspin at all costs, since that increases our acceptance window.  Slice is the best since that reduces our acceptance window the most.  If we can't slice the ball for some reason, flat is the next best thing.

Where should we stand for groundstrokes?  The closer in the better.  Our acceptance window increases as we move back behind the baseline, so try to hold that baseline and hit balls inside the baseline whenever possible.

Since we're inside the baseline, should we take the ball on the rise?  Absolutely, for two reasons.  First, taking the ball on the rise makes it very hard to hit topspin, which we noted above we definitely want to avoid.  Second, if we take the ball on the rise, especially just after the bounce, we can strike the ball down around our knees, or even lower if we can short-hop the ball.  The higher we strike the ball the larger our acceptance window is and we want to keep that window small to keep our margin of safety as low as possible.

How about changing the direction of the ball?  Change it.  Sending the ball back where it came from dramatically reduces left-right errors, again increasing the margin of safety.  Changing the direction from a cross-court ball that crosses your body by going down the near line is a great way to reduce your margin of safety.  And since you're going down the line, make sure to hit the ball very hard.  The high velocity ball down the line has a much smaller acceptance window than a ball played back cross-court or to the middle.

So, there you have it, a great recipe for playing low margin-of-safety tennis.  Hit balls low and hard to the deep corners, using slice or no spin.  Make sure you take the ball early, on the rise, and inside the court, if possible.  Take cross-court balls down the line.

To play high margin of safety, just invert the above paragraph.

There are many ways to tennis heaven, and playing low margin-of-safety is one of them, though I see many more successful high-margin-of-safety players at all levels.  But you gotta do what you gotta do.  My guess is if you love the low margin game, I'll be seeing you in the back draw.