Jim, Denny, Bob, Gerald, Pat, et al
Not taking sides on the discussion, but for those who disagree with any portion of the 921 document, recall the last sentence in the following "ACCEPTED" statement in 2004 edition:
"1.3 Application. This document is designed to produce a systematic, working framework or outline by which effective fire and explosion investigation and origin and cause analysis can be accomplished. It contains specific procedures to assist in the investigation of fires and explosions. These procedures represent the judgment developed from the NFPA consensus process system, that if followed can improve the probability of reaching sound conclusions. Deviations from these procedures, however, are not necessarily wrong or inferior but need to be justified."
Just my Nickel (as there is a plan to abolish the US penny)!
Chris