Along the same lines, what about sub and sup? To me, they seem 
dangerously close to presentational markup, unless someone can enlighten 
me as to what the semantic meaning of these two elements is...

The examples given at 
http://www.w3.org/TR/xhtml2/mod-text.html#sec_9.12 . aren't making it any 
clearer:

H<sub>2</sub>O
E = mc<sup>2</sup>

Surely this should be marked up more rightly with something like MathML?

<span xml:lang="fr">M<sup>lle</sup> Dupont</span>

As the line just above the example states: "Many scripts (e.g., French) 
require superscripts or subscripts for proper rendering." So, 
"rendering" to me again suggests visual, unless you're suggesting that 
if "lle" isn't set as sup (when other forms of styling are 
disabled/unavailable), Mlle loses its meaning (which I'd contest).

P
-- 
Patrick H. Lauke
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