Question about include element and existing specializations

Proposal #8 to add the <include> element also covered an update to coderef, svgref, and mathmlref so that they are based on <include>.

I've been working on integrating that change into the technical content specification this evening and ran into a question.

The proposal mentioned adding @parse to those three (with default values), but overlooked adding the other new attribute @encoding from the new base element. This pretty clearly seems to be an oversight (no reason to exclude it), so I've put that onto the three existing elements.

One question I'm wondering about -- with these three currently-empty elements now based on <include>, they could also allow the nested <fallback> element for cases where backup behavior is needed. 

Should that element be added as a child to those three, or should they be left as they are today? I'm not sure if this was an oversight in the proposal, or was explicitly left out.

Thanks,

Robert D. Anderson
DITA-OT lead and Co-editor DITA 1.3 specification
Marketing Services Center

E-mail: 

11501 BURNET RD,, TX, 78758-3400, AUSTIN, USA