First and Third
Runner on first steals to bait a throw so the runner on third can score.
How it actually works. The offense sends the runner from first. If the catcher throws through to second the runner on third breaks for home the moment the ball passes the pitcher. The defense has four answers and each concedes something: throw through and take the out at second while risking the run, hold the ball and concede the base, throw to the pitcher cutting it off in front of second, or make the short throw to the shortstop moving in behind the mound, who looks the runner back and then decides.
Why it is done, and when it is wrong. Everything here comes down to the score and the inning, and this is one of the clearest places in baseball where the same play is right and wrong depending on nothing but the scoreboard. Down four in the third you take the out every time and the run is meaningless. Tied in the eighth you concede second base without a thought, because the out you would gain is worth far less than the run you would give up. A defense that runs the same answer regardless of the score is not running a strategy, it is running a habit.
What people get wrong about it. The runner on third is the one to watch, not the runner going. Good third base coaches teach an aggressive bluff, a hard three steps and a stop, specifically to make a catcher hold the ball. A catcher who has been frozen once will hold it the rest of the game.
At Little League and travel ball. This is the most productive single situation to practice in youth baseball, and it is close to a free run at most levels because the cut man is not in place and nobody has decided in advance what the answer is. Deciding in advance, in the dugout, before the inning, is the whole coaching job here.
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