I really, really, REALLY hate threads like this, because 20 of the replies could have been omitted with google.
Even though everything I was gonna say has been said, it should be mentioned...
Battlezone/Battlezone 2: There was a separate view that you could use, called satellite uplink I think (though I know it was in Mechwarrior, maybe it was in both...) after you created a communications relay.
In BZ, you could get out of your vehicle and get in other vehicles, but that was pretty much the only reason to be an infantry-man. To steal other vehicles by sniping enemy pilots in their cockpits.
In BZ2, you were able to get out of your vehicle and go inside buildings as well as use your jetpack, or get different weapon loadouts from your armory (there was one with a bazooka and some other stuff) but the MAIN thing I meant to say was that you could go inside your communications bunker and that was where your RTS view came from - using the computer in there. You can give orders, leave, get in a tank, and join the assault yourself!
In Savage 2, (probably savage 1 too but I never played it...) one of the players DOES play as a commander, having very little abilities to assist the battle. He has is non-combat and combat buffs, like heals or armor buffs, or making one person do more damage for a few seconds. Other than that, he separates players into groups and squads, provides them orders that they don't usually listen to, he can build buildings on his own but players who picked a worker class (think battlefield or TF2 on respawn) can help construct it faster or create buildings themselves if their commander is incompetent.
In games like Mechwarrior, you have a top-down view that you don't use much, and can give basic orders to people, but it's nothing on the scale that you guys want or are talking about.
I hope this post sort of enlightens someone, I guess.