Richard,
Given that those particular two variation selectors have already given
very specific semantics for emoji sequences, and would now be expected
to occur *only* in emoji sequences:
https://www.unicode.org/reports/tr51/#def_text_presentation_selector
usurping them to do something unrelated would probably not be a good idea.
For experimentation purposes, VS13 and VS14 would be safer.
--Ken
On 1/25/2020 10:41 AM, Richard Wordingham via Unicode wrote:
How inappropriate would it be to usurp a pair of variation selectors
for this purpose? For mnemonic purposes, I would suggest usurping
FE0E VARIATION SELECTOR-15 for *1A8E TAI THAM SIGN INITIAL
FE0F VARIATION SELECTOR-16 for *1A8F TAI THAM SIGN FINAL