Internally, SET can always be implemented as atomic variant of REMOVE-then-ADD.In general yes. However for the Jackrabbit Microkernel use case this becomes troublesome wrt. observation.The diff format makes no promises about the observable events, so I wouldn't worry about that.
What I'm worrying about is that when the format doesn't allow us to implement JCR observation, we won't use it but rather a derivative of it.
Michael
