Doesn't mater. In coaching, you always want guaranteed money and years. It really has nothing to do with desires/intentions... it's a volatile business, and if someone is offering top tier money for a bunch of years you take it. If you get fired, you still get paid and can look elsewhere. And it gives you long term leverage... if you're sitting in year #2 of a 10 year deal and they're on the hook for $40mil more you can go into your boss's office and say "I WANT XYZ!" and they have to listen because they still owe you $40mil. If you're in year #2 of a 2 year deal they can tell you to go screw yourself.
If you really don't think you want to stay, then you have a reduced buyout clause for leaving for another job such that another team is willing to pay it (i.e. the team poaching you only pays $2mil of your $5mil a year). That's pretty typical.
Oh, absolutely. It's far less potent than having a big *** offer in hand, but it's wayyyyy better than no leverage at all. Saying "look, I'm willing to entertain offers from NFL teams and they have interest in me as evidenced by this interview and I've had other teams contact me too... but I'd really like to stay here." + having a "reported" second interview setup after his vacation to add a sense of urgency is a FAR better position to be in than "so I had a really good season... out of the goodness of your heart can I have a raise? Oh, and a raise for my assistants? And these changes?"
And honestly sometimes going so far as to get an offer in hand is dangerous brinkmanship if you don't actually want to leave... if you say "give me XYZ or else!" and they tell you to go pound salt... you basically have to take the offer.