The heaters probably utilize a thermo-coupler. It has to be heated to release any fuel. You find them on pretty much any indoor gas appliances. I don't think removing them from the system is a good idea. Natural gas is heavier than air so it sinks. The though of a big balloon of gas (the pocket being trapped under the shield) being exposed to a flame (the lighter) sounds like a recipe for a Youtube video. Please post it.