Interesting - I'm not sure that mobile networking really has massively overprovisioned bandwidth, but satellite and radio links might. Can you think of a way to identify these links so that similar techniques can be deployed when they are found?
Also, this scheme is not really asking for massively over provisioned lines; we're looking at fairly small data sets with infrequent bursts to larger sets, and an ack from the receiver knocks the size back down again.
That said, if I were implementing this, I would probably implement a sliding window for messages I send (waterfall encoding would work great here, though it is patent encumbered), and add the ability for the client to request a set of messages it missed. This would make the traffic a bit more predictable and offer the server & client the ability to make up for traffic which was lost during its send window.