• 9.6 baseline — 0.6 × season 8.7 (20 gm) + 0.4 × last 10 10.9
• +0.6 opponent leak — they concede 365.4/game vs a 344.7 league average
• at this ground: too thin to count (3 gm) — shown, adds nothing
• vs them: averages 12.4 over 8 games — evidence, never summed

Derived, not measured — plain arithmetic over his real games, shown in full. Adjustments can overlap (a game at this ground can also be a wet one); they add simply, and this note is the admission. Round 11: 33 — far outside his usual range; kept in the average, not smoothed away.