Provided someone justified their opinion, theres would over-ride mine.
That should be 'theirs'.
And I would in a cockpit or any other workplace.
You shouldn't start a sentence with 'and'.
And experience, from say a captain, would be sufficient to do so AND has been sufficient to do so up to now.
This sentence doesn't make sense.
If you're going to be a spelling and grammar nazi then at least make sure your own is perfect, eh?