For what it's worth, my experience in the last several months is that much of these cancellations of flights, re-routes, etc., relate more to the lack of passenger reservations than it does with anything else. I went to Puerto Vallarta in August and, originally, was to have a 1 hour layover in Houston. But, when I arrived to my airport of departure, I was told that the layover would be 9 hours in Houston as a result of the cancellation of the flight that I was originally booked for.
I will also be flying in to Santiago next month and the flight that I had originally reserved to leave out of JFK at midnight has now been scrapped and I was booked on an earlier flight to Santiago, and have to leave on a much earlier flight for my departure back home. I did notice when making the original flight that there were not many reserved seats.
So, Im inclined to agree with HOWMAR, in that much of what you see relates more to a lack of reservations than it does any issues with fuel.