The spec states that there MUST be a corresponding notification when the state of a resource changes as a result of an HTTP operation.
First, seek clarification: What is the definition of 'state' of a resource?
Secondly, check/audit the current impl behaviour. At the very least, it seems to emit too many message under some circumstances. For example, if you modify A with a PATCH so that it links to B, there will be two "resource modification" messages: one for A, and one for B. It is unclear if B is warranted.