• 10.6 baseline — 0.6 × season 9.5 (21 gm) + 0.4 × last 10 12.2
• +0.3 opponent leak — they concede 558/game vs a 544.2 league average
• −1.9 at this ground — averages 8.7 there (12 gm)
• wet forecast: too thin to count (3 gm) — shown, adds nothing
• vs them: averages 8.0 over 2 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 15: 27 — far outside his usual range; kept in the average, not smoothed away.