That's certainly part of it, but I can't tell you how many kids I've seen be way too predictable by not varying their time to delivery and sometimes just not looking over. Son's team had multiple occasions where they had running starts. They even did it to lefties a couple times.
We spend quite a bit of time working on stealing 3rd by having our runners study pitchers. Most pitchers are very predictable with holding runners on especially with a man on 2nd. If done correctly the catcher shouldn't even throw the ball to 3rd, as the runner basically steals it standing up.
I have always coached that fundamentally sound teams are very hard to beat.... and giving up multiple free bases is a sure way to end up on the losing side.