19 -> ~16 was wrong. Ran the actual normalizeSupplierName() (trim +
whitespace-collapse + uppercase) against the three example pairs cited
as evidence: only the case-variant pair (Builders Warehouse) actually
collapses. The Ikhasi pair keeps a stray space after a hyphen that
differs between variants; the Global Precast pair differs by the
"(Pty) Ltd" suffix, not case or whitespace. Neither collapses under
exact-normalized matching.
This is not a defect -- it's the conservative-matching principle in
section 3 working as designed. The correct expectation against
production is 19 raw strings -> 18 groups, one merge. Both pairs that
don't collapse are exactly the kind of ambiguous case the spec already
says should stay separate for a human to resolve, not the kind that
should be forced together by loosening the normalizer.
Caught while grounding the implementation plan in real data, before
writing a single line of the plan itself.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>