Here’s a query: I know that I’ve read one or two articles somewhere in which someone proposes to abbreviate a pair/set of segmental (i.e., non-stress) rules by means of the parentheses notation, where the notation must be interpreted not (simply) as marking optional material, but in the way that it is for abbreviated stress rules: longest expansion first, disjunctive blocking else removal of innermost parenthesized material, repeat. But I’ll be damned if I can remember anything more concrete than that — the rules or the sources. I don’t even know whether I can concoct a hypothetical example that would clarify things better. Anyone know what I’m talking about?

Immediate update: OK, I can come up with an entirely hypothetical example. It’s one I’m sure is impossible, but it’ll at least clarify things.

The hypthetical rule is a weak cross between pre-nasal vowel nasalization and the Latin stress rule (assume allowance for any number of intervening non-nasal consonants anywhere in the rule, just to avoid that complication).

V → [+nas] / __ ( ( V ) V ) N

If the parens are interpreted in the usual stress-rule way, the three subrules are:

1. V → [+nas] / __ V V N
2. V → [+nas] / __ V N
3. V → [+nas] / __ N

Subrule 1 gets a shot first, then 2, then 3. If any subrule applies, the others are blocked. The result is that in representations with three pre-nasal vowels, only the first (furthest from the nasal) will be nasalized; otherwise, in representations with two pre-nasal vowels, only the first (furthest from the nasal) will be nasalized, etc.

That’s a ridiculous rule, but I’m still fairly sure I remember reading somewhere about a much more plausible/real example of parenthesis-induced disjunctive blocking of non-stress rules.