I'm sure the green tankers make it worse, but I ran some tests, of T72s vs the Brit tanks, and found that they can easily win a 1 v 1 head-on duel provided they have pre-knowledge of the opfor unit. They also need to hit it below the turret. I achieved the pre-knowlege with close by scouts (probably any unit will do, and alternatively by dismounting the tank crew so they could see for themselves. Ran them back into their tank, drove into LOS with my hatch open, and more often than not got the kill. Transferring this to a live battlefield with lots of opfor units is problematic, but if you can find a keyhole with LOS, and/or a hull down position to fire from, I'm sure it will work. They just gotta know the other guy is there before they engage.