I seem to remember that even in Bach's B minor mass (where E12 was not
yet a thing) there is an enharmonic tie (or at least tonal repetition?)
in the transition from "Confiteor" to "Et expecto". I mean, that
transition is a tonal center nightmare anyway.
In bar 138:
Basically that is an example of enharmonic equivalence of diminished 7th
chords: The tonal centre in the preceding bars is clearly d (d major
with hints of d minor), so the diminished chord in bar 138 is most
probably first heard as f♯-a-c-e♭ (with expected resolution to g minor),
but is then being re-interpreted (and written) as f♯-a-b♯-d♯, resolving
to c♯ major functioning as a dominant to f♯ minor.
My point is: Even without E12 tuning, this is clearly an example of
fully exploited enharmonic equivalence used as a "wormhole" in an
otherwise purely diatonic tonal system. There can be no question that
this is semantically a tie.
(One might raise the objection that, maybe, when performing the piece, a
slight adjustment in intonation might be needed in the transition from c
to b♯. But this can also happen for bona fide ties in purely diatonic
music, so that does not yield an argument against the tie being a tie.)
Lukas
