The discussion is engaging, but won't help find 447. So, I'll join in and suggest that information can be sent to satellite as a stream of hundreds of parameters that would moot the discovery of any boxes. Setting the transponder, or an automatic signalling when the Bus changes flight Law could break the dam and immerse a receiver with all pertinent trails. There is very near enough in ACARS to speculate within a narrow band.
Is there will in the industry? With all respect, AF and its cousins are not working their hands to the bone, and it would be a most naive partisan to say the will is powerful to locate. That 447 was out of touch is indicative of a "don't ask, don't send" attitude; Some sleeping dogs are encouraged to remain sleeping.
I am sending this message on a private system that sends enormous bags of data to a satellite, to another satellite, thence to Georgia, (US), then to Santa Clara, then back to me, in nanoseconds. Let's stop challenging windmills and ask some pertinent questions instead.
There is a system that can ionize air (airflow) intermittently, release it, to be captured, tagged, and computed as airspeed down the fuselage and sent to the Cockpit in the same micro seconds. Pitot smeet-o.
The Dark ages have never been beaten back whilst profit can be managed as a result of Risk/Benefit analysis.
bearfoil