Routine Violations: Violations which are a habitual action on the part of the operator and are tolerated by the governing authority.
Exceptional Violations: Violations which are an isolated departure from authority, neither typical of the individual nor condoned by management.
The Reason Model, does indeed allow that deliberate violations fit into the accident investigation paradigm.
Obviously some here believe the first was in play whilst others believe the second.
SIUYA-WHY was there a failure to follow MITCOM procedure?
The straight answer, when I discussed it with the certifying engineer, was that he couldn't give a fluck, he had been doing this for years and CASA could do the other thing. Now of course putting this in a response would mean he would have been given a show cause by the regulator. This is covered by part two of Reason's violations.
Creampuff, I think your razor is getting blunt. Okham's Razor tells us the simplest answer is probably correct and to avoid complicated reasoning.