You, Sir, are 100% correct!
Get the heck out of the kill zone rikky-tick, or charge and advance on those trying to kill you and kill them first.
Vehicles are magnets for all kinds of incoming fire!!
I have recovered 230 grain FMJ .45cal rounds from the engine compartment-AFTER they have entered the trunk, passed through, traversed the passanger compartment, went through the dash and came to rest on the engine block-and this was from a Caddilac.
Yeah, vehicles can make good concealement, but are lousy cover.
Unless the group is trained as single unit and there are heavy and crew served weapons, you're not likely to gain fire superiority.
You'll need to learn to move in groups, supporting each others "bound" or travel-and use the terrain, crossing danger zones at different times and using shadows, on and on, but the article IS a good start...

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