Would be a nice idea for those interested in pursuing greater understanding of the Halchos being discussed to study the sources inside. To understand Rav Ahron’s shita, please see his teshuva in Shu”t Mishnas Rav Ahron. Good place to start.
It’s interesting how many people commented how “they don’t know why Rt 9 would be different than any other road wider than 16 Amos”, and then proceeded to disparage the idea. It would be far more intelligent to actually find out the answer….