Simon,
Some questions for you.
As you look at the route flown....what Class Airspace was it along the route....plainly it changed several time?
In each Class Airspace...what was the "VFR" minima for the operation considering both FAR's and the Operator OpSpecs?
If the Weather in Controlled Airspace is 1000/3sm....that is VFR...right?
Marginal.....depends upon your definition but in general I agree with you....depending upon that the forecast is and what the actual weather is in the surrounding area along the route of flight.
If the weather plummets to 900 feet ceiling down to 2.5sm vis.....and becomes IFR in controlled airspace....and the flight is continued via SVFR.....is that not still VMC flight under IFR?
What are the weather minima for Helicopters flying in SVFR within Controlled Airspace?
As to flying from VMC into IMC....if not done intentionally....is not a rule violation.
Perhaps he realized the best option was to declare his intentions and climb to VFR on Top.....why would the FAA see that as a violation?