Peeps in charge of this investigation think they know a lot but they still aren't 100% sure. Obfuscation began when Flight 370 shut down its transponders/comms and turned West. Until the Black Boxes are located on the sea floor by their acoustic pinging the investigators won't know for sure. Speculation only takes you so far and then you need to sit back and rethink -- what is real? They're only part-way through the "what" and "where", and much less than that on the "who" and "why". I think they know "when".