I just had a high-powered private investigator look at a fire I investigated recently. In my report I said there was more than one failure that cause the fire. I said there were three different factors. The first was the human element, which altered the system as it was designed. The second was a failure in the blower motor, and the third was a failure with the high-limit switch. The high-limit was found in separate pieces so I could not say if it coming apart was the failure or it failed to operate as designed.

I must admit I do not like being laughed at and told I am stupid. This expert said it is extremely rare to have multiple failures that result in a fire. I was also told I did not know what I was talking about with regards to the high-limit switch. He said these switches are designed to operate over 100,000 times before failing. He also said these switches falling apart during a fire is common.
I have always been taught that fires originate, for the most part, because of a sequence of events coming together at the right time. I guess what I am asking is does this person have valid reasons to say what he did?