I’ve read all 5500+ of the posts to this thread, and I’m struck by the lack of known facts. Focusing on position, the last known position we know for certain is where MH370 was when its XPDR went dead. Many theories have been set forth on what MH370 did next. Please allow me to offer one that I haven’t seen presented yet.
Consider that a primary radar return signal has no inherent identification data in it. Thus, one knows the “where” of the target causing the return, but one don’t know the “what” or the “who” with certainty. This leads to the possibility of spoofing. Admittedly it wouldn’t be easy, but it might offer an explanation why only the MAF’s primary radar seemed to detect MH370 - they were following a false trail. The spoofing signals might also explain the wild altitude excursions the MAF reported for MH370.
Similarly, the Inmarsat pings could be spoofed. If the SATCOM on MH370 was turned off, someone could be located anywhere along one of the famous red arcs, responding to the Inmarsat ping on an hourly basis using the electronic identity of MH370’s SATCOM. Again not easy to do, but if someone did they could create yet another false trail.
Why go to the trouble of spoofing radar and satellite signals? Possibly because it would let the real MH370 go east, where no one was (or is) looking, buying time for the perpetrators to do...something.