[tei-council] @who="all | various | unknown"

[Martin Holmes]

One bit of my birthday chapter 
(<http://teijenkins.hcmc.uvic.ca/job/TEIP5/lastSuccessfulBuild/artifact/release/doc/tei-p5-doc/en/html/TS.html#TSBAUT>) 
says, regarding the <u> element:

"Use of the @who attribute to associate the utterance with a particular 
speaker is recommended but not required. Its use implies as a further 
requirement that all speakers be identified by a person or personGrp 
element in the TEI header (see section 15.2.2 The Participant 
Description), but it may also point to another external source of 
information about the speaker. Where utterances or other parts of the 
transcription cannot be attributed with confidence to any particular 
participant or group of participants, the encoder may choose to define 
‘participants’ such as all or various, or unknown. "

@who is 1–∞ occurrences of data.pointer, so clearly its values cannot be 
"all", "various" or "unknown", unless files with those names exist as 
siblings of the file containing the @who.

I think I know what this means: encoders should create e.g. <personGrp> 
elements with @xml:id="all", "various" or "unknown". But I don't think 
this is clear enough in the prose of the chapter. If I have understood 
correctly, or misunderstood, please let me know. Either way I'll expand 
this paragraph to clarify what strategy is actually being recommended here.

Cheers,
Martin