What is meant by "rather inefficient"? Speed of serializing/deserializing?
That also, but my understanding is that python-jsonrpc only supports single-request-per-connection HTTP/1.0, whereas jgarzik's bitcoinrpc supports HTTP/1.1 persistent connections.
Why do we even recommend JSON-RPC at all?
It's not even an official library for Python and it isn't very good (uses floats and has no persistent connections). We should only be recommending jgarzik's version.
Who recommends it? The proposed summary clearly recommend jgarzik's fork. It
is an official library
for JSON-RPC.