• 1.1 baseline — 0.6 × season 1.3 (8 gm) + 0.4 × last 10 1.0
• +0.0 opponent leak — they concede 351.7/game vs a 344.7 league average
• +0.9 at this ground — averages 2 there (4 gm)
• vs them: averages 5.5 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 12: 8 — far outside his usual range; kept in the average, not smoothed away.