There's one thing I will agree with: to figure out the fate of the plane we have to get inside the pilot's head and try to figure out what he's doing. The trick here is that based on the available facts, we have to stop thinking in terms of someone who's trying desperately to save the plane and his passengers, and try to understand someone's whose goal is to do the opposite.
One thing to think about- where would you crash a plane if your goal was not simply to crash a plane, but to conceal its fate? Whoever took the plane seems to have wanted its resting place to remain a mystery. They must have known that the path of the plane would be tracked by military radar, so by heading northwest until they were off radar, and then turning southeast, they must have wanted to mislead searchers about the direction of the flight. And by sending the plane into the deeps of the Indian Ocean, they must have hoped that the wreckage would never be found. But one thing didn't make sense here. If you were going to go to this kind of length to lose a plane forever, where would you crash it? Not southwest of Australia; the sea there is deep but its a fairly broad and flat ocean floor. Yes the search area here is huge and the seas are rough, but if the wreckage ends up on a flat expanse of seafloor, it's going to be pretty easy to spot on sonar. It would take a long time to find, but eventually it would be found. No, you wouldn't want an abyssal plain. You'd go for the deepest, most rugged stretch you could find. You'd pilot the plain straight into an ocean trench.
Then a curious thing happened. The search area was changed, again, for something like the third time. The new data suggests the plane didn't fly as far, and instead of crashing southwest of Australia, it crashed almost due west of Australia. At first this seems to suggest the search will be easier. But if you look on the maps, you'll see that the new search area overlaps an ocean trench- the Diamantina Trench, the deepest point in the entire Indian Ocean. Its maximum depth is 8,000 meters/26,000 feet. Eight kilometers. Five miles. Its rugged terrain, which will conceal the plane and scatter any noise from the sonar beacon. Plus, the Navy's pinger locator can only go about 6,000 meters down, and the range of the black box ping signal is only about a mile, so if the plane is at the deepest part of the trench, it's may well be out of the range of sonar equipment. On top of everything, the terrain is going to be unstable; unlike a flat abyssal plain where the sediments accumulate slowly and don't shift, the mountainous terrain of the Diamantina Trench will be subject to slumps and debris flows, with avalanches of fine mud that could easily bury a plane.
Up until now, it seemed like a good bet that the plane would be found, eventually. After all the Titanic was sitting on the seafloor for the better part of a century before it was discovered. But if the pilot really did crash the plane into the Diamantina Trench, there's a real chance that it's lost for good.