You know - the last few sentences kinda invalidates the believability of this story. But with the median IQ of the population being 100 - that puts half of us in the "stupid" range of the IQ scale. With that, it doesn't totally surprise me that someone would be dumb enough to coat a roof with gasoline and light it to get the roof shingle set. It sounds like something my brother, the king of jerry-rigging (also the guy who once sprayed his kid's ass with Lysol to kill the smell while changing his diaper) would do.
Anyway - major roofing projects in the winter was never a good idea. They're building a new house not too far from here as we speak - in single digit temperatures. I can't imagine that will be good for the roof as summertime is really the ideal time to replace a roof.