The protocol currently requires reftype and reftarget to be included in any responses to COPY requests on collections that contain references. This has the consequence that even if the COPY was completely successful, a Multi-Status response must be returned. Yaron is concerned that some non-referencing clients may break as a result, because they will assume that they will get a simple 201 response if all went well. This is related to Issue 11, which points out similar problems with including reftype and reftarget in responses to LOCK requests. The protocol tries to follow a general policy that whenever a client submits a request to a reference, it should be made aware of that fact.
More discussion is needed.
On one hand, you expect the result to be an independent resource that can be modified without affecting the source. These expectations may conflict. Unix by default copies the target, not the hard or soft link. Maybe we should take the point of view of the site administrator, whose interest is in keeping down-level clients from messing up the site. COPY may be one of these.