In section 3.8.4.2, there are sentences like the following:

* if M is a model group which obeys the Unique Particle Attribution (§3.8.6) constraint

But UPA only applies to content models (the *root* particle of a complex type), not model groups.

* some sequence S of element information items has two ·paths· in P (where P is a particle)

But "path" (follow the link) is defined in terms of "in a model group M".

* For example, in the content model
* By contrast, in the content model

The examples (<xs:sequence> or <xs:choice>) aren't necessarily content models. Should use either "particle" or "model group", depending what the definition of "compete" is really for.

* Two (or more) ·paths· of a sequence S in a Particle P

Again, "path" is defined for model groups.

* For any sequence S of element information items and any particle P, a ·path· of S in P

Ditto.


Seems that the rest of the spec needs concepts like path, validation-path, compete, UPA, ... for particles (and content models); but what's established in earlier parts of 3.8.4 only covers model groups.

Maybe at least the concept of "path" should be re-introduced for particles, after the 3.9.4.1.1 material. And update links from the above cited sentences to point to the particle-path, as opposed to the model-group-path. But then it seems 3.9.4 becomes a better home for 3.8.4.2, as it's mainly about particles, not model groups.