RE: [CTG] Draft 2008-11-07 / inconsistencies / validation

> Consequently, in order to satisfy the need to give
> excellent end-user experiences, we must (sadly) adjust
> our adapted output to suit the quirks of the requesting
> device, thus addressing the bugs/features that
> we know to be present.

You are actually raising two points:
a) extensions to existing standards (i.e. additional features that are not captured by standard W3C, IETF, etc formal specifications);
b) errors, i.e. deviations from the supposedly supported formal specifications.

Regarding point (a), vendors usually make available a formal definition of their extended features (otherwise how would developers use them?), but we can admit that there is no general guarantee that there is a published formal specification that can be used for validation.

Regarding point (b), you are thinking about issues like, say, a browser that accepts <p> inside <div> but not otherwise, although this is possible as per (X)HTML DTD. This is the nasty part, and I agree this is usually deduced from  testing, not from some formal spec. 

Can we state that the transformed content returned to the terminal must at least be well-formed (following XML terminology)?

E.Casais