A key question for me has not been resolved to my complete satisfaction. I'm hoping someone here can answer it, as I am not a pilot. I believe absolute key to Vette's position is his view that INS is as reliable as ground based aides. Is (or was) this justified, given the conditions at the time? I know some have answered "yes," and others "no." If the answer is "no," then why not? My common sense speculation has been that INS is less reliable for precisely the kind of mistake that was actually made in the last minute change of coordinates.
Thanks
[edit: changed "unreliable" to "less reliable"]