"Clinical systems SHALL use the specification defined by US Core in exchanging information with payers"

1. DTR doesn't involve sharing clinical information with payers except temporarily through adaptive forms.  (And in that case, they're not using the US Core spec to do so.)
2. We don't want to limit the ability of the CQL to only US Core data.
3. Expectations around support for US Core should be reflected in the CapabilityStatement for EHRs
4. Conformance statements don't belong on background pages

Drop this, set expectations for US Core support in the EHR and SMART CapabilityStatements.  The only addition that might be useful is - in the section on CQL design - say something like "CQL that queries EHR systems SHOULD limit itself to the resources and search parameters defined in U.S. core and SHALL gracefully handle the failure to execute any non-US Core based query."