We've decided to extend the existing XSLT rather than create a new file and duplicate code, so <segs> in <pron>s will now be handled by the same transformation that handles <phr>s in <quote>s. The bones are in place, and the existing code is still working well on our test set with the empty branching in place to support <pron>s. The test set has been extended and we've already got a long regex to match the range of prefixes which will serve as a surrogate for the more convenient morpheme delimiters.

One final step: the collapsing of duplicate <phr> elements, which is currently handled by an external post-transformation, needs to be brought back into this single file, so that all the changes required are done at the same time.