4.1 Server Discovery - Mixing Normative/Non-Normative

The section starts with normative text, switches to non-normative and then back to normative. To illustrate:

This Endpoint provides general information about a TAXII Server, including the advertised API Roots.
(ok, that's normative)

It's a common entry point for TAXII Clients into the data and services provided by a TAXII Server. For example, clients auto-discovering TAXII Servers via the DNS SRV record defined in section 1.4.1 will be able to automatically retrieve a discovery response for that server by requesting the /taxii/ path on that domain.
(Clearly non-normative, "common entry point," "for example,")

Discovery API responses MAY advertise any TAXII API Root (included those hosted on other servers).
(normative)

I would make the middle section a note.

BTW, are you serious about "any TAXII API Root?" I ask because some TAXII servers may wish to conceal their APIs until after non-TAXII authentication. Your call but it looks like a TAXII API could "out" another TAXII server's APIs.