my mom was just the other day telling me about a relative who lost their relatively-newly purchased home to a chimney fireOh man! We heated with wood for a long time, and I'm glad to not have to cut wood anymore. We had one chimney fire in a chimney that wasn't even close to being blocked, and we were lucky that we could get the fire out before it could spread. I remember that it sounded like a jet engine with the after burner kicked in.
I think you were extremely fortunate to not have ever burned the house down.