We will expand the language about what a server should do in situations where it is unable to perform some (all) of the population or extraction capabilities (i.e. return warnings or errors in OperationOutcome). Will also define what the potential behaviors are when control logic is not supported (i.e. enableWhen, defaults). (i.e. do you prevent authoring, prevent setting to 'complete', etc.) We don't know that most systems will have a choice of what server they're going to perform extract/populate with. In theory, R5 will have better support for this sort of thing, but we won't be able to access it in R4. Will create a tracker that has us revisit this once R5 is out and CapabilityStatement is (hopefully) more 'capable'.