The error is the win at all costs teaching technique used by the coach. This is how winners do, or you are a loser. You want to know where this comes from, just look at the coaches setting such a great example for your child, and the parents condoning this type of coaching technique, because these are the things that get you ahead in life, and get you that look at me, look at me, how great i am, that all winners in the game of life have, or should have and aspire to, so you don't get left out in real life.
So, to me, you would not have to even need a rule about this, if I were a coach. Number one, I as a coach (and that is why I would never be asked to be one in a competition environment i would imagine), i would not coach this type of tactic even though I would be violating the athletic/competition code of, if you ain't cheat'in, you ain't trying.
the above would be told at the beginning of the year in a meeting with the players and the parents. I would also mention to the parents that winning at all costs was not in my vocabulary, but I would be fine with anyone that wanted to find another League or team that did not share my views.
if I caught my player doing this, and I would catch it before the umpire, believe me, I would remove the player and we would have one last talk about why that strategy would not be acceptable sportsmanship, with the warning that the next violation, strike 3, (remember strike one was at the beginning team meeting with the parents and by not leaving then, you were in agreement with my thoughts on sportsmanship and fair play), and removal from the team. You would not need this rule with me, nor would the umpire need to deal with any sneaky attempts at avoiding the spirit of the rules.
Now if you want to keep the player in the game with the current rule, just make it so the umpires move the violator back a base, just like getting knocked back in a board game. If a runner is behind the runner being sent back, that runner is declared out, and removed from the base due to the violation of the lead runner being penalized. The player is warned and so is the coach. Further transgressions by any player for this same violation are ejection from the game for the coach. If the same player violates a second time for this same violation, that player is ejected. Life does not have to be 3 strikes and you are out in all instances, even with baseball.