I have to assume that investigators have listened to any and all ATC transmissions which occurred at about the same time which communications were lost with MH370. I bring this up because as many of you may recall when TWA 800 was lost, there were some pireps which witnessed the moment of the explosion or shortly thereafter. Assuming for a moment that there was an explosion involved, if traffic nearby didn't witness any anomalies (would it be due to the time of day (less traffic)?