What are current perspectives on analyzing word-final /i/ in English words like "potency" as synchronically derived from /j/?

Question

I have encountered, I believe mostly in works from Generativist phonological traditions along the lines of Chomsky and Halle's The Sound Pattern of English, the idea that words like potency, latency, decency, presidency end at some level of morpho-phonology with the sound /j/ rather than some nuclear vowel sound like /i/.

I've realized I don't quite understand the point of this analysis; could anyone explain it to me and tell me if it is still considered to be correct by anyone, or by most people, or by only a few people?

Stress & vowel length

The main motivation that I think I understand is stress and vowel length: if we say that "potency" has only two syllables at the level of phonology where stress and vowel length rules are applied, this explains why it doesn't show "trisyllabic laxing"/"Luick's law" and has a long rather than a short vowel in the initial syllable. Likewise, the stress of "presidency" can be analyzed as antepenult rather than pre-antepenult. However, this seems kind of a lame motivating factor in itself considering that there are many other extra-metrical suffixes in English that aren't, as far as I know, analyzed as lacking syllabic nuclei, such as -ness, -less. Also, I know of at least one exception to the apparent extrametricality of -y in -ency/-ancy nouns: the word discrepancy, which is typically pronounced with antepenult stress on the e, which is "short". It seem to me that it would be bizarre to explain this by saying that "potency" ends in /j/ but "discrepancy" ends in /i/.

Apparent consonant changes

I suppose another reason might be the apparent palatalization of /t/ to /s/ in these words (latent > latency). While palatalization is undoubtedly the diachronic source of /s/ in words ending in -cy, it is not obvious to me that we can explain the /s/ as the result of a synchronically active process of palatalization.

Palatalization before written "i"/phonetic /i~j/ in word-medial contexts usually yields /ʃ/, not /s/ (or at least can): consider potential, potentiality. Unlike these words, potency cannot be pronounced with /ʃ/. This suggests to me that "potency" has to be analyzed somewhat differently.

Also, we see /s/ in -ance/-ence words, where there is no (at least, no overt) following segment corresponding to /j/.

There are also odd formations like normalcy < normal, where there is no /t/ in the source word; baronetcy, with /t/ followed by /s/; and, in spelling if not in pronunciation, also bankruptcy, vicountcy, paramountcy. These examples suggest that in at least some cases, /si/ is apprehended as a suffix, in which case "ancy" and "ency", rather being analyzed as -ant + -y and -ent + -y, can or should be analyzed as -ant + -cy and -ent + -cy, with no need to consider the /s/ as derived synchronically from palatalization of /t/.

Answer 1

For the most part, phonologists aren’t invested in the analysis of classical SPE issues of English phonology (e.g. the supreme ~ supremacy relationship, idem professsor ~ professorial). When these relations are analyzed, this is mostly carried out within Lexical Phonology. The primary reason why these relations are no longer seen as central to the concerns of phonology is that the sound patterns are not clearly part of a system of grammatical rules (which is what most phonologists are interested in) with a reasonable degree of generality. Because there is the viable alternative of simply saying that “supreme” and “supremacy” are separate words, each of which has to be learned (i.e. there is no rule), we can say that [ɪj] and [ɛ] as stem vowels are part of what you learn when you learn the words “supreme” and “supremacy”. Under SPE-era analytic standards, there was a feeling that all ‘linguistically significant’ generalizations had to be captured in the formal grammar, whereas now there is more tolerance of leaving some generalizations to be captured by linguistic theories outside of grammar (especially by historical linguistics – “because that word comes from Latin, where it was pronounced X” is a possible answer).

Since the possibility of affixing, the choice of affix, and pronunciation of resulting form is somewhat word-specific, there have to be separate lexical entries for “supreme” and “supremacy”, and we no longer view grammars as data-compression devices (whereby you can only have one root underlying a half-dozen words). In some cases (e.g. un-, pre-, -ing, -s, -er, -ness… affixation) there is good reason to claim that we are looking at current rule-governed behavior, but that cannot be said about supreme / supremacy and ilk.

There aren't opinion polls taken of the International Phonologists' Society (which does not exist), so it is hard to say how many people do still believe in the program of reducing the size of the lexicon even when relations are not fully predictable. Based on what I know of phonologists' thinking, I believe that most people don't presume that there are such synchronic relations.