bankmeadow - re your 7138.
It is really quite simple. The BOI stated that "the forecast weather was suitable for the Flight but would have required flight in accordance with IFR in the vicinity of the Mull of Kintyre".
To put that another way "the forecast weather was suitable for the flight but would have precluded flight in accordance with VFR in the vicinity of the Mull of Kintyre."
Both those statements have the same meaning in Flight Safety terms - as they approached the Mull they should have been at or above Safety Altitude until they were unequivocably certain that the en route weather ahead was suitable for low level flight at high speed.
Before we get into the argument that SH do not operate that way, let us be quite clear that this was not an SH Task but a routine Passenger Transit Flight utilising In Theatre SH assets.