sbslider wrote:It says that either bag can be used if there is a errant throw...
Close, but you needed to read just a little bit further!
What the rule says is that "On an errant throw pulling the defense off the white portion of the base
into foul ground" the defense and the batter-runner may use either base.
The intent of this rule isn't to let the defense use the orange bag on a throw that is just off the mark and requires the fielder to take a step toward the orange bag. It is meant to cover a play where the fielder is drawn completely off the base into foul ground.
If the fielder was all the way over in foul ground, and was still required to cross back over the orange base to get to the white one, the safety base isn't quite so safe anymore. You have just put the batter-runner and the fielder on a criss-crossing collision course!
So, if the fielder is all the way in foul ground, the rule allows her to use the closest base- the colored one- instead of running into the path of the batter-runner. The batter-runner has the option of continuing toward the safety base, since that's likely the one she would have been headed for in the first place and we're not going to penalize her for doing what she is supposed to do and not altering her path due to the defense's bad play, or using the white base since doing so might very well avoid a collision with a fielder who is suddenly in her way.