• 1.3 baseline — 0.6 × season 1.6 (17 gm) + 0.4 × last 10 0.8
• +0.3 opponent leak — they concede 29.9/game vs a 23.6 league average
• vs them: averages 0.9 over 9 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 9: 12 — far outside his usual range; kept in the average, not smoothed away.