Wouldn't upper cylinder lube like Lucas or MMO eventually live at the bottom of the gas tank? I once added MMO to a half-empty tank, then topped off. My car immediately started running very rich with fuel trims in the high negative 20's. It evened out shortly afterwards, but that was enough to give me pause. I'm guessing there was a glut of MMO right near the inlet of the fuel pump. Also, if you use this stuff regularly, wouldn't it continue building up in the bottom of the tank and either never get burned, or eventually reach the fuel pump and make bad things happen? Thoughts?