Back in the 1980s I first started playing the thoroughbreds at Fairmount Park, and found it quite a bit more interesting than betting the jugheads (harness).
One night while a buddy of mine and I were standing outside watching the post parade, he suddenly said, "Come on, I'll buy us a beer." We walked back inside, but then my buddy stood some distance away from the bar, and explained he was watching one of the trainers for a trainer's "go" signal, which included having his picture taken in the winner's circle with a fresh beer in his hand. The trainer bought a beer, and headed back outside. My buddy went to place bets for us, gave me $10, and had me buy the beers.
The trainer's "fresh beer" angle came through, and the horse won, as my buddy used to say, "like a thief in the night". At 5 or 6-1 if IIRC. I thought I was on to the road to riches, if all I had to do was watch trainers. I had already learned to watch the harness drivers as they warmed up, and noted which ones studied the tote board as they drove by.
Then my buddy informed me that that trainer was the only one who used the "victory beer" angle, and he only won about 10 races per season....
