With all due respect to R99, my understanding is that the F-106 is a remarkably capable jet that handles very well at slow speeds. I do not believe that the F-106s that were attempting to trail 305 that night had a problem with the 200 MPH speed. I think there is more to the story.
That said, the fact that Cooper wanted the lights out in the jet probably did have to do with the possibility of the jet being chased. After all, when the airstairs extended downward during Cooper's jump, this would have been quite visible by a trailing jet if the lights were on in 305's cabin.
You may have hit on an important distinction. lights out in the jet on the ground vs in the air. On the ground makes sense - in the air who is going to be looking? It could go to Cooper's background, his experience, possibly his training, ... perhaps tactical training or just somebody rather bright. Not your typical food service employee?
Why did a search turn up no military records? Maybe they focused too much on sky divers and not enough on retired tactical fighter pilots? Or tactical planner types, or disaffected systems analysts and mathematicians? Somebody sensitive to all the pieces in a puzzle, or a chess match.
Ive always wondered why H had a almost visceral reaction to this Unsub. H was trained as a fighter pilot although he never saw any combat. H turns around and calls C a nasty ... food service worker type! He might as well have said 'a dumb son of a bitch ...even though Cooper is outwitting everyone!' Did H sense one of his own kind was at work and was competing with him personally'?
We have to be very careful that we don't create paradigms that may not be true!
What I am suggesting here is the FBI may have looked in all the wrong places with the wrong profile for Cooper, just as in the Unabomber case. Kaczynski got found but he essentially revealed himself just as McCoy did ... it just took longer to nail down Kaczynski. They both had the same big ego and big mouth! If Cooper survived to have a long career, what did he do with it?
I dont think this was Cooper's first rodeo - or his last! I dont think a mere $200k assuaged Cooper's "grudge".