[aback]

First off, the numbers I cited were not theoretical, they were the observed network run rate at the time I posted.

Secondly, Bitcoin doesn't have to scale up to Visa levels, at least not in 2016. In 2016, it just has to scale up. And there's plenty of room to scale up.

Bitcoin has a growth plan that subsidizes the expansion of the network (via inflation and adoption) for many more decades. In two decades, the Moore's Law equivalent of a 1MB block size is a 16GB block size. Even without additional scalability, Bitcoin can process a lot of transactions with 16GB blocks.