Glyphs: modifier turned glottal stop vs combining right tack

[drammock]

According to our old diacritics spreadsheet, ˤ and a̙ (without the a) are featurally synonymous (+RTR -ATR), but the modifier pharyngeal is for consonants and the combining tack is for vowels. This convention is not followed in the UPSID data, where segments like ãõ̞ˤ occur in !Xu. However, since the latter half of that segment already has a lower diacritic (combining down tack), adding a combining right tack makes it hard/impossible to read.

Maybe this is a non-issue since there seems to be some changes afoot in the UPSID data (possibly done by one of @bambooforest's UZH minions?) that includes getting rid of the downtacks for vowels described simply as "mid". So two related questions: what is the story with those UPSID changes? What to do about the modifier pharyngeal on vowels in UPSID?