I know wheels have many mechanical advantages. The problem is that wheels are the thin edge of wedge. They enable stupidity.

Allowing infantry to carry more weight, by allowing wheels, means that they will be get even more overloaded. Man-packing is a simple and coherent method of forcing the argument back to basics, as is Mules or Llamas, or even well trained Hamsters.

We want to try and avoid making doing stupid things possible, because history shows that Infantry Officers always overload their men - almost always because of stupidity, and a failure to ask the right question in the right context.

I also submit that a well trained and well lead army does not have load carrying problem because it has already exercised the judgement necessary to avoid it.