Schwa-heavy phrases pair only with parallel phrases

A phrase run with <2 full vowels can't barge into a word family
("Two bitches" -> the Tuna chain) but may pair with a structurally
parallel phrase (clock's ticking / stop tripping).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app.py

@@ -709,10 +709,12 @@ def analyze(draft: Draft):
         for t in g["toks"]:
             if " " not in t["word"]:
                 grouped_spans[t["line"]].append((t["start"], t["end"], gi))
+    by_par = defaultdict(list)
     for p in phrases:
         if p["weak"]:
             continue
         vs = p["vowels"]
+        full = sum(1 for v in vs if v not in REDUCED)
         if len(vs) >= 3 or (len(vs) == 2 and vs[1] not in REDUCED):
             key = _multi_key(vs)
         else:
@@ -725,6 +727,12 @@ def analyze(draft: Draft):
             # anchor + schwa-tails ("Sleep is the") prove nothing
             if sum(v != "x" for v in key[2:].split()) < 2:
                 continue
+        if full < 2 and not key.startswith("m2:"):
+            # a schwa-heavy run can't barge into a word family ("Two
+            # bitches" -> the Tuna chain), but parallel phrases may pair
+            # with each other (clock's ticking / stop tripping)
+            by_par[(p["sid"], key)].append(p)
+            continue
         spans = grouped_spans[p["line"]]
         a_gi = next((gi for s, e, gi in spans if s <= p["start"] < e), None)
         b_gi = next((gi for s, e, gi in spans if s < p["end"] <= e), None)
@@ -746,6 +754,12 @@ def analyze(draft: Draft):
             continue
         attach_or_collect(p, key, by_multi, group_by_multi)
 
+    for (sid, key), toks in by_par.items():
+        toks = [t for t in toks if id(t) not in grouped]
+        if len(toks) >= 2 and len({t["word"].split()[0] for t in toks}) >= 2:
+            raw_groups.append({"toks": toks, "slant": True, "key": key})
+            grouped.update(id(t) for t in toks)
+
     # biggest buckets claim first (a token may sit in several via its
     # anchors); distinctness by anchor word, so the phrase "fire burns"
     # can't pose as a different word than the "fire" it starts with

tests/test_rhymes.py

@@ -470,3 +470,10 @@ def test_weak_endings_never_split_rich_chains():
             "You no wan' start Weezy 'cause the F is for finisher")
     group_with(text, "charisma", "patricia", "militia",
                "commissioner", "finisher", "spritzer")
+
+
+def test_schwa_heavy_phrase_cannot_join_word_family():
+    # "Two bitches" (UW + schwas) must not ride the Buddha/scuba chain
+    text = ("doin' it like Buddha, scuba, Cuba\n"
+            "Two bitches at the same time")
+    assert "two bitches" not in highlighted(text)