profile= parameter for RDF 1.2 media types

Hi,

while considering the compatibility between RDF 1.1 and 1.2 software, I
came across the notion of RDF profiles defined in [1].

I am wondering how applications should treat the ambiguity of the media
types of the standard RDF serialisations, especially when doing HTTP
content negotiation: If a server software emitting RDF data is asked for
such data, it would be helpful to know whether the client can handle RDF
1.2 or not.

If a client, by specifying a header like "Accept: text/turtle; profile=basic",
declares that it doesn't support triple terms, but the graph data I am
to server is known to contain triple terms, my server could reply with
406 Not Acceptable instead of generating triple data that the client
won't be able to understand anyway.

Cheers,
Nik

[1] https://www.w3.org/TR/rdf12-concepts/#conformance