Just a quick comment on uniqueness...
An attribute may be unique without being required. In HTML, the 'id'
attribute is meant to be unique and may be applied to any element. It is
used to select zero or one element, but not more than one, for example, a
specific DIV element. Of course, not all DIV elements need have an id. The
uniqueness simplifies programming in that there is no need to loop through
more than one element. It also provides validation where having more than
one element with a given id would be illogical or inconsistent.
As to whether 'context-group' should have a unique 'name' or not is a
different matter. The name, however, may be both unique and optional.
I took a quick look at the PO profile and didn't see why the context-groups
had the same name. I thought it might have been given the same name just
because the name attribute was required (in XLIFF 1.1) and so some name had
to be given.
As for wishing to be able to select multiple context-groups, assigning names
with a common prefix allows for easy selection using an XML processor. The
XPath would include "@name[starts-with('my-prefix-')]".
I can go either way, but prefer changing the profile to conform to the spec.
A tool reading an XLIFF document may rely on the uniqueness of the 'name'
attribute.
Regards,
Doug Domeny