> W.r.t. ‘Create Split Key’, you misunderstood: Judy Furlong points out that the specification neglects to state that ‘Create Split Key’ [and some other new operations] sets the ID Placeholder.
Again a deliberate choice - as Create Split Key will generally return more than one unique identifier so the ID Placeholder is not set (unlike in Create Key Pair where there is only a single private key returned so the logic sort of made sense to set the ID Placeholder to that value even though there are two unique identifiers returned). But Create Split Key returns multiple unique identifiers to objects of the same type so there is no "special" one to select out as being the right one.
The whole context of ID Placeholder is to support logical chaining of operations in a single request within the limited set of contexts which made sense to the specification authors at the time.
Tim.