A loss of cabin pressure at “under the radar” altitudes wouldn’t be bad.
Which would explain why the original Boeing report was denied by the investigators.
They may want to buy time to find the plane before whoever took it knows they are on their trail.
Form the article: "Boeing declined comment."
Even if it was possible, explain how the transponders were shut off. Both of them. The engines on the Boeing 777 emit a signal via satellite so it will alert the maintenance shop of problems for repair before the plane arrives at Bejing. That signal indicate the engines were running for 4 hours after the plane radar blip disappear. This will also corroborate with the Chinese families ability to call their love ones, hearing ringing on the cellphones, but no one answers. If the plane had crashed into the ocean, the cellpones would not ring but immediately inform the caller the cell is not available and refer to the owners voicemail to leaving a message. This is one of the weirdest air incidents to date especially in the age where everything can be tracked.