Re: can it be done?
 

I think it could be done.
The BF2 engine does support bullet penetration to a limited extent. What I don't know is how far this extent is. It might only allow it on static objects, in which case we won't be able to use it on tanks. It also might only alow it ont certain types of weapons, ie small arms fire. This would mean that you can shoot through walls with a tank gun.

I'll have to experiment with the physics when I get the game, but the bullet penetration does give more options for realism.