Welcome to Battlefield Singleplayer. The Source for Battlefield AI!
for the interior part: if you play 2142 or bf2, then go for example to a humvee and shoot against the glass from outside, doesnt matter if you shoot in front of it or behind the humvee where you can look inside the humvee. anyway, you shoot against the glass and you see a bullethole, now enter the humvee and you wont see the bullethole. and now imagine this happens with all the stuff going on: if you are inside a humvee driving it and people shoot against your humvee, you will miss alot of stuff like hit effect, bulletholes and even if they hit your car interior while you are sitting in, you wont notice it nor will you see any bullethole or hiteffect while the players outside will see it and hitting a guy inside a vehicle is very bugged, sometimes the bullets goes through him. same when someone use the gun of the humvee or pickup or tank, you will notice that some bullets will go through him, even if you hit him 100%