Here's a little story... brief version:I was helping defend our base from incoming mammoths. I was in a light tank zooming out to attack and then back in base to repair, which works well with the speed of light tanks. Anyway, I see that the closest mammoth has no one it in and the engineer is running around repairing it. I drive up to the mammy, ditch my light tank, and hop in the mammy (and squishing the previous driver of course). One of my teammates was even observant enough to notice what I was doing and ran up to hop in the light tank to bring it back to base.
But wait.. it gets better. This all happened just feet outside of our base. Since the mammy was severely damaged, I immediately started heading back to base. Upon entering it, someone in a mobile artillery starts shooting at me and this is a friendly fire game. I had not fired a single shot at anyone yet. I drive down next to the obelisk and hop out, assuming that he's notice that a teammate got out of it and no one is currently in it. Nope.. still keeps shooting at the tank. I'm an engineer, so I was repairing the tank by this point but I had one problem... he wouldn't stop shooting it but I couldn't talk or else I'd stop repairing. Eventually (since he was doing more damage than I could repair) I said to stop (another teammate also yelled it), but alas it got in the last few shots to destroy it.
It always feels good to steal a mammy, but I'd rather be able to actually use it afterwards.