If you don't know, there is a highly sophisticated US naval air facility on the island of Diego Garcia. The Navy does deep space reconnaissance over there! among other things...
And they didn't detect a massive 777 flying north/south in and around the Indian Ocean?
That area is saturated in complex radar. Diego Garcia houses complex radar and satellite communications systems and who knows what else that is still classified.
Additionally, there are over 1,000 operational satellites in orbit!
IMO, this was a carefully and planned mission.
For all we know (tin-foil hat time) there could be behind the curtain negotiations with hijackers and/or missions being planned to recover the aircraft in case of wild extremists theories flying around on the Internet (0.1% on this) And as we all know today, nothing is that extreme anymore in the world we live in.
Disabling transponders takes three clicks of a wheel and it was most definitely done intentionally, the sharp, almost hairpin turn, this jet made and then strategically avoided radar are all signs of a sophisticated operation here. The WSJ reports that circuit breakers were accessed in order to shut down transponders, clearly requiring a high level of skill for aircraft maintenance opps. Sure, pilot can break a circuit but they will spend 20 minutes reading the flight maintenance manual AND contact ground before doing anything like this.
Finally - there were a few important people on board, including quite a few high-tech people involved with government contractions.
Whatever is happening, it might never make complete sense - or at least the general public might be out the loop and get whatever information THEY want us to hear. I don't know who THEY are but this whole situation is very strange and gets crazier by the day.
Edit: this bird was hacked