I have a few substantive comments that I hope can be entered.

2.3 Purpose - Syntax
I think this should be the WG's option to specify either free-form hypertext or constrained plain text. This document should provide the guidance that the Purpose string may go into various tools and reports and should be appropriate for all that the WG reasonably expects will be used.

2.6 SpecRef - Syntax
When I think "ideally" about this item, I think XPointer should be used. Does anyone use XPointer?

2.7 Preconditions - Rationale/SeeAlso/Comments
Another thing that is NOT a valid use of preconditions, besides setting parameters, is specifying filtering criteria as a precondition. Have a SeeAlso pointer to Grouping as part of the contrast. For example, it is wrong to say that test w6231 in the XFoo suite has a precondition that the product under test must implement the Placid module. Preconditions are tasks to do or situations to set up that are particular to an individual case, derived from test assertions that have contingencies about the environment or about prior actions. Preconditions are instructions to the test harness or person executing the test, and should be independent of the product under test.

2.10 Version - SeeAlso/Comments
Have a SeeAlso reference to SpecRef, and a comment that since most W3C technologies attempt to be forward-compatible across newer versions of the spec (and higher levels if they use levels), it is desirable that test cases support that notion. Ideally, a test case will not need to be revised to apply to the next version of the spec. Hence, this "Version" datum always refers to the test case itself. Each WG should define SpecRef and possibly other metadata (Grouping or their own metadata items) to express which spec versions the test case supports.

Acknowledgments
Please change my corporate affiliation to "IBM Research".
.................David Marston