Redrafting the third part of the article encouraged me to do even more refinement of the schema; I've now nailed down the use of @type and @subtype more thoroughly, and tweaked the encoding of <gloss> as a result. It uses @subtype="i" instead of @type, for consistency with <seg> and <phr>, even though it makes no use of @type (at the moment). The article is coming along, and I hope to get the first draft of my bits finished tomorrow.