And the flying club I have been working at part time for the last few years used to be one of those that ran RAF Cadetship courses. One of the ex cadets from the club is now flying GR4's. All the instructors were civilians, all were checked each year by CFS.
There are some very talented people in civvy street. The forces are not the preserve of talented and skillfull aviators. A friend of mine started as one of the above instructors, went on to fly Twotters for two seasons with British Antartic Survey. Kind of develops skills in navigation, airmanship and captaincy, the kind of things that need instilling in new entry air crew in the military.
Having looked at Ascent website they are looking to "challenge the status quo". The "most civvy FI's wouldn't last a day" kind of attitude is precisely one of the reasons I left in the first place - the "I've been in the service longer then you so I know better" attitude. Does that attitude still prevail?
If you have that kind of attitude in commercial flying these days you won't pass a CRM course and won't get, let alone last a day on the line.