BF2S Forums Can't grasp the Engineer Class

Seems like the team I'm on likes the Jolly Roger, it's like a magnet, also seems like the enemy can see them and bypass, but the team I'm on can't and they can actually see the skull and crossbones. Well when I put mines down I usually have one that is blocked off and one that is not, that way the "team" can go around. Or like when I got kicked for excessive tk's, we had one flag and put mines because of "enemy armor spotted" coming our way, I was figuring that our tanks would fall back and let the enemy come blazing through, so I hide by the mines  and low and behold our tanks are the ones storming towards the enemy so I decide to wrench on my mines to get them out of the way, not only does he kill me by running over me, but he and another tank went over them, mind you the tanks were well enough away to see everything, and besides we had another flag to capture behind us. This is just one scenerio. I'm just saying it's frustrating being an engineer for me other than in a BH. What really is the engineer used for? CQC mainly. I can't survive long enough in a tank to get out and wrench on it, once in a blue moon maybe. But when commander wants repairs/or anyone, usually I run from one end to the other to repair and either they are dead or the commander set the box there already. I put mines down and tanks/aircraft/apcs/c4/grenades can blow them up. Maybe I am playing the class wrong, how can I make the engineer class productive?