Leave it to a jar head not to comprehend simple analogies. Draw out a diagram showing the forces acting on an airplane. The one that pushes from the front is called drag. Therefore, anything pushing back against the aircraft's forward movement is drag, i.e. a conveyor belt moving 300 mph. It sure as hell isn't gravity, lift or thrust. If there was no thrust from the engines, the aircraft would move backwards at 300mph. The aircraft would not just sit there in one spot, unless you had frictionless wheels. If that's the case, then the treadmill is pointless anyway - it's not exerting any sort of force on the airframe. In order for an airplane to take off, thrust must overcome drag by a given amount. This generates lift which overcomes gravity. Next you're going to tell me that if I can an ostrich on a treadmill going fast enough, it will fly. But it's easy to just make statements with any explanation to back it up - just like a jar head.