That's correct AlaCowboy. I believe Steve is referring to when a ball expires just as it is hit on the green. You'll be informed that your ball was replaced before you strike your first putt. I've had that happen to me before as well.
The one thing you don't have to be concerned about is wear from the putter. Even though the ball is replaced on the green in this situation the hits do not deplete unless you knock it off the green or until you reach the next tee (where the ball would normally be substituted as per the rules).