WD01 shows a use case (client networking configuration), but then discusses a strawman (HTTP). Pub/Sub with correlation can be used to do the Request/Response pattern, not precisely in the manner anticipated, but functionally useful.

A description of why typical patterns such as private topic use for request/response do not work should be included.

The document does not convince that there's a real problem that needs solution with a change to the MQTT 3.1.1 specification.