Cheng's ideas focus on reducing latency by reducing the number of round trips a packet takes.
Latency is defined as delays in the network. ISPs using bufferbloat, described by Jim Gettys as the condition " whereby excess buffering of packets inside the network causes high latency and jitter." Basically, network devices are making incorrect decisions on whether to keep or discard packets. Given that memory is relatively cheap, these devices are storing large amounts of data in the buffer. Under load, the network may take longer to process the request as the the buffer must clear to service the new request. In networks with bufferbloat present, the full benefit of Cheng's proposed improvments may not be realized.
Interesting comments on Cheng's blog.