DiagnosticRequest.code 1..1

In Europe, a lab request usually orders multiple tests and panels for the subject.
V2 accommodated this requirement, with field ORC-4 "Placer Group Number", enabling to group multiple OBR/ORC pairs.
V3 enabled an observation in RQO mood to include other observations in RQO mood.
FHIR DiagnosticRequest misses this capability, currently.

A diagnostic request should be able to group multiple diagnostic services (e.g; CBC, Urinalysis, chemistry panel, serology panel) ordered as one coherent set authored by the requester and requested to the same performer.

One proposal to enable this is to set the cardinalities of DiagnosticRequest.code to 1..*, provided this does not break the workflow resources logic.