I have to say I agree. I can't see what the problem is. We used to have a CAA FOI fly regularly with us in order to maintain proficency on type. They would attend all annual training courses and provide us with their previous 28 days duties before arriving to fly.
The only stipulation that we had was that they flew with an LTC in the RHS. This was purely because we felt that a non-employee of the company should not be 'commercially' in command of the aircraft.
We have never had a problem with the situation. I guess if you don't have anything to hide and are confident in the proceedures and systems you have in place making you a safe operation then why the reluctance to let an FOI near yur aircraft!
