The simple fact is that those vehicles exist in one form or another right now. Do you remember watching the shining when the old guy was tring to get up to the hotal before Jack hacked up the kid, remeber what he was driving a tracked vehicle. In the movie Tomb Raider when Angelina and freinds went to the dead area, remember the tracked vehicles that drove thru the freezing ocean then back onto land with their tracks, remember the half track vehicle of WWII fame. Those are all tracked vehicles and there is a reason they are avoided in todays army with the exception of the tank. They are not efficient, their milage sucks compared to wheeled vehicles. Yes you can make a claim and you are correct they can turn on a dime, and not worry about a pot hole (or a small bombshell hole), but unless you have come up with some new and significantly improved design that has not been tried by every industrialized countries engineering workforce for the last 67 years. If you are going to design a viable product in the engineering field, it has to be able to be constructed, it has to be an improvement over what is already available, and it has to be cost effective (in the practical sense it has to cost less than what is currently availble).