[House Rules] Are vehicles really diging in?

[Hugmenot]

Prime movers cannot dig in.

16.23 Cavalry and transports can't dig in.

1.2 Definitions. Transport Units: Vehicles used to transport personnel units and leaders, or tow crew-served weapons. This includes wagons, trucks and sledges. APCs are combat units which can act as transports as well

It would be even clearer if prime movers were added to the "wagons, trucks, and sledges" list above.