Inmarsat said the new technology – called SwiftBroadband-Safety (SB-S) and dubbed the “black box in the cloud” – could prevent a crash by speeding up communication between the cockpit and the ground in the event of a mechanical problem or terrorist incident.
Hmmm... What communication does Inmarsat think will be enhanced in the case of a terrorist incident? How many terrorists (or Captains of victim airplanes) have attempted ANY communication that would be "speeded up" by this system?
I will admit that there may be SOME benefit in locating an airplane that has already crashed, and in analyzing causes of a crash. However, any "prevention" of a crash would be limited to measures implemented that were ONLY detectable by the system.
Take the case of AF447, for example. How many crashes were there between the time of that crash and the time the FDR and CVR were found? How many were caused by pilots who froze on the controls after a high-altitude stall? How many would have been prevented if we knew that earlier? Has AF changed their training, or has Airbus changed their control laws as a result?