Even if everyone on the plane were deceased, the phones which were left on should have picked up the network at 5,000ft over the Malaysian Peninsula. The fact

Even if everyone on the plane were deceased, the phones which were left on should have picked up the network at 5,000ft over the Malaysian Peninsula. The fact that they evidently did not connect to their networks is... yet another mystery. It's possible that phone jammers were used. Either way, mechanical failure theories can't explain the lack of phone-network connections (fire disables all aircraft communications AND all cell phones AND doesn't destroy the plane? Bizarro). Hijacking theories technically can, but only tenuously (jammers? seriously?).