Throughout the modern history of American racing, handicapping methods have changed remarkably little. The memoirs of the legendary gambler Pittsburgh Phil, written in the early 1900s, disclose that he stressed the importance of class and physical condition, watched for larceny by jockeys and trainers, and computed speed figures. Serious horseplayers continued to operate in a similar fashion for more than half a century.

But a revolution is taking place in the handicapping world. Astute bettors are using an approach that would not only have been foreign to Pittsburgh Phil, but also was almost unknown just a few years ago.

"Ten years ago," said a professional gambler who asked anonymity, "there were only two of us in New York who knew anything about trip handicapping--and the other guy eventually lost his mind. What a time! You could make more money than the president of the United States if you knew what you were doing."

Five years ago, I first started hearing some sophisticated New Yorkers talk about "trips." And now the majority of serious, professional horseplayers probably would characterize themselves as trip handicappers.

What they do, essentially, is watch races closely and make visual judgments of the horses' capabilities. This may not sound particularly revolutionary, but the approach is based on a new philosophy of the game.

Traditionally, handicappers have judged horses by the outcome of races. Speed handicappers look at the final times; class handicappers look to see who has beaten whom. Trip handicappers believe that the finish of a race may be deceptive or irrelevant, because the outcome of a race is determined by the way that race develops. My anonymous friend would deride my simplistic reliance on speed figures. "I don't care how fast they run," he said cryptically. "What matters is how they run fast."

Handicappers of every era have understood the importance of watching races, of spotting horses who are blocked or checked or put under a hammerlock by a jockey. But the new generation of trip handicappers finds significance in the way every horse ran his race. They believe every horse's performance must be judged in the context of his trip. And with the advantage of closed-circuit television replays, which weren't available to horseplayers a generation ago, they have the chance to observe every horse in a field.

Why has trip handicapping suddenly become so popular? The reason, oddly, has been the influence of harness racing. As the standardbred sport has grown, a significant number of bettors have gotten their first exposure to racing from the trotters and pacers. Anyone who spends even one or two nights at a harness track learns quickly that the best horse doesn't necessarily win. If an eight-horse field produced a particular result one week, and then was rematched the next with the horses starting from different post positions, the results would probably be very different.

The outcome of harness races is greatly influenced by loss of ground on the turns: a standardbred who is forced to race wide on both turns of a race has virtually forfeited his chances to win. The early pace also has considerable effect on the result of a race. A horse who battles through the first half-mile in 1:01 may collapse; if he gets to the lead in 1:03 he may be able to whip the same group of horses. Racing tactics are also crucial; a driver has to stay out of trouble and make his move at the optimal time.

The importance of trips is much less obvious in thoroughbred racing. In my first 15 years around the track, I don't think I ever heard a handicapper say he preferred a horse because he had to race very wide around the turn in his prior start, while his principal rival had managed to get through along the rail. But the graduates of harness tracks who made the transition to thoroughbred racing came with a fully developed appreciation of the importance of trips, and they used their knowledge profitably.

The majority of successful professional bettors I know are trip handicappers with a harness-racing background, and their performance has verified the validity of their approach. Serious horseplayers should at least consider adopting some of their methods. To do so, however, they must acquire a new set of skills and learn a new language.