The pitcher's time to the plate is really the determining factor in the college and pro dugout on when to steal. The time starts the instant the pitcher moves, and ends when the catcher catches the ball.
An average time to the plate is between 1.3-1.5. With this time to the plate, and the average pop time of a high school catcher (2.15), the baserunner must get to second base in at least 3.45 seconds if the pitcher is a 1.3, or 3.65 if the pitcher is a 1.5. This is very doable b/c that is with the catcher throwing a strike to second.
I don't know about the high school level, but, from a standard lead, our JUCO guys that are base stealers will reach second in about 3.4 seconds. Remember the average college catcher has a 2.5 pop time.
Usually, if a guy slide-steps, his time will be around a 1.1-1.2. If a guy slide-steps occasionally, don't go if he slide-steps when you are attempting to steal (unless the hit and run is on, of course).
Lefties are a whole different breed. Their times will usually be around 1.6-1.8, unless on a slide-step. The key with lefties are to determine whether or not he is a "Reader" (decides to pick at the top of his leg kick).
If this is the case, there are two determining factors on whether or not to steal. You need to know what his time is on a pick-off (it will usually be a little quicker than his time to the plate). If his time to the plate is 1.6, you can expect his pick-off to be around a 1.4-1.5, if he is a reader. One, how athletic is the first baseman? Is he left handed or right handed? If the first baseman is not very athletic, and the pitcher's pick-off time is around a 1.5-1.6, if you go first movement on a reader, you have a pretty good chance of beating the throw to second. Remember, the first baseman has to move-in toward the mound, and throw a tagable ball away from the base runner.
Another thing to focus on with a "reader" is to begin the time-to-the plate at the top of his leg kick. This way, you can make sure that he is going to the plate, and steal second successfully. I his time to the plate, based on first movement, is a 1.7, from the top of the leg-kick, it will more than likely be around a 1.3.
A lefty that is not a "reader" should be judged the same as a righty.
All of our baserunners know exactly what each pitcher's time to the plate is before they step into the box... As the first base coach, and base running coach, I always remind them of it when they reach first.
I know this is a lot of info. but it will really help you steal bases if you know the pitcher's time to the plate.
I hope this helps, please feel free to ask if you have any questions.
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