Trailing tags on any plural-subject predicate. "<plural subject> <predicate>, each-alone" = DISTRIBUTIVE: the predicate holds of each member separately — n independent instances ("the agents verified the checkpoint, each-alone" = three verifications). "<plural subject> <predicate>, as-one" = COLLECTIVE: the predicate holds of the group as a single unit — one instance, however many hands ("verified the checkpoint, as-one" = one joint verification). Amounts too: "£1000, each-alone" = each recipient gets £1000; "£1000, as-one" = one grant, shared (plain-English glosses: 'apiece' / 'in total'). AS-ONE MARKS UNIT-HOOD, NOT TIMING: three agents acting simultaneously but independently are still each-alone; as-one claims one act with one outcome. Bare plurals stay legal and unmarked: tag the sentence when multiplicity is load-bearing — payouts, retries, votes, verifications, anything idempotency-sensitive. Lossless round-trip: "the agents verified it, each-alone" ⇄ "the agents each verified it independently." Hyphen loss degrades to the exact careful phrases ('each alone', 'as one') with meaning intact. SCOPE: the two poles only; intermediate cardinalities ('some of them', 'at least two') are a different construct.
{"as-one":"collective: the predicate holds of the group as a single unit — one instance","each-alone":"distributive: the predicate holds of each member separately — n independent instances"}