Sounds like a good explanation of what Jane Fonda's VC and NVA did. ;-(
You all are right but for some overlooked things. Some terrain has limitations for the operation of these vehicles and the main one is the number and availability of these assets. It is spelled out in unit Tables of Organization & Equipment. For example: Right now, in the present situation, you might have a use for say... 400 of these type of vehicles. In budget projections there was only enough money to finance say...ten of these. You have to also be able to finance other equipment that has a higher probability of use- like a tank or something.
If you had enough equipment around to cover every type of potential need the defense budget would be HUGE.
It is just a part of military planning. You have to utilize what you have to cover all contingencies. Equipment is just a part of the overall planning.
That's why, in this case, you just don't swoop in with the right numbers of proper equipment because it just isn't available. The only other choice would be to just "hang loose" while the new ones are being built and shipped to you. Not very practicle.