> On 21 Nov 2013, at 22:10, "Stuart A. Yeates" <[log in to unmask]> wrote:
> Is it your contention that all valid P4 TEI  documents became 'not TEI' overnight when P5 was released? That all documents that were once valid against the then-standard but are not valid against the current standard are 'not TEI' ?

They are TEI P4, sure. But not "TEI".  P4 went out of support this year.

Don't get me wrong, a TEi p4 doc is a very good thing to have, as is a TEi p3 sgml doc. 
Just don't expect them to work with generic "TEI" tools without going through an upgrade process. And we shouldn't suggest newcomers mine them for good practice in encoding.

I think our friends in Docbook are in a very similar position.