I would agree that if you're already chugging along and a belt would to snap, it would take no time at all for the engine to overheat, whether or not you're good at looking at your gauges or not. I've had two cars near overheating before, and luckily I caught both of them by noticing either a hissng sound or steam when I came to a stop. If I would have been on the highway, I am sure there would have been some real damage. The light just really isn't enough cruising around during the daytime. Who checks their gauges THAT often?