What changed
EOSIO: speed came from a short list of producers.
The paper trades open membership at the block level for a delegated set. Who sits in that set is the system.
Original thesis
Delegated proof of stake, resource accounts, and a constitution. Throughput is the headline. The producer schedule is the mechanism.
What changed
A small producer set can be fast and can be captured. Later networks forked the software. The brand and the code diverged. Cite the document, not the ticker.
What remains useful
Any design that publishes a short validator list should be read as a governance design first. The transactions per second are the consequence.