ASE is an interesting place. If I was a fed and needed a little help reaching my monthly violation quota I wouldn't even bother checking guys just as they are getting ready to leave Aspen. I've get them as they were taxiing in. I'd be comparing their landing weight with the data from their approach climb charts.
This.
At towered airports, it ends when cancel IFR or land full stop and taxi in and tower cancels for you. Anywhere else, it ends when you cancel IFR.
Correct philosophically, although the mechanics may vary.
At one time evidently you could get a "through flight" clearance (I think that was what it was called.) that allowed you to make an enroute stop without getting another clearance. I had ATC offer one to me once when the weather was down and there was no easy way to pickup a clearance on the ground. The controller cleared us to our ultimate destination "through" our fuel stop. We were on the ground long enough to pick up our company execs and take on a bit of fuel then we simply took back off and contacted ATC. No muss, no fuss. In 35 years, that has happened to me exactly once. I don't know if it's even available now.
Heh... well, whatever you folk in that fancy tall building do.
(My joke was that there's some action up there that finishes off the flight plan, but you magicians handle that stuff...)
In a combined TRACON/Tower, that's essentially correct. Where the Tower is not the IFR control facility, say, at Salisbury MD, the tower controller has to pick up the phone and tell the IFR controlling facility (Patuxent Approach, in the Salisbury case) you're on the ground. In any event, it takes an act by tower to cancel the IFR clearance in the system, and if they don't do that act, there's nothing to prevent doing a T&G and staying IFR -- happens all the time.
I can't speak to the flight plan filed with FSS, but until Tower calls Approach and says "he's on the ground," the TRACON cannot clear anyone else into that airspace, and they must keep the missed approach airspace clear.