[PA Engineer]

I agree with you.

My first thought based on the debris field was an internal explosion then break up during descent.

Based on the plane track and emergency call, I don't believe it broke up initially. Sadly, I think it broke up during the emergency decent and the passengers were aware of what was going on.

I agree with the BBC interview (scroll down): Mikael Robertsson from flight tracking service Flight Radar 24: ''This was something more than a planned diversion''

[TXnMA]

The description by Mikael Robertsson of "a sudden drop in speed like a stall" and "up-and-down motion" is not inconsistent with the behavior of an airframe when it has lost the tail -- or control of the aft control surfaces...

I'll have to go listen again; I didn't know there was an "emergency call"...

Thanks for the feedback and the link!