.... taking us nicely back to Tapper's dilemma. Most military pilots plan (expect?) a VFR-to-IFR low level abort to result in an IFR transit for the rest of the route. To say that the SA around the Mull was 2400ft and therefore the pilots could have climbed to SA within the RTS is misleading. Once he had gone IFR, Tapper's only expectation would have been to continue IFR, all the way. Of course, this option was not available to him because the aircraft was unfit for the task (icing clearance).
So, put yourself at Aldergrove the day of the crash. You have a routine SH (not passenger transport) task with an aircraft that has limitations imposed upon it. You check the weather and realise you need an IFR option. You ask for another airframe - not available. Who is the tasking authority and what will their actions be if you refuse the task. Your only real option is to go VFR all the way. The odds were stacked against John and Rick before they even walked to the aircraft. Of course, you could say that they should have done a 180 as the approached the Mull maybe climbing to an IFR SA of 2900ft, returning 25 peeved-off very important people, together with their golf clubs, back to the dispersal at Aldergrove. But then human factors start to take an increasingly important role in the whole event.