• 1.0 baseline — 0.6 × season 0.9 (15 gm) + 0.4 × last 10 1.2
• +0.0 opponent leak — they concede 12.5/game vs a 12.2 league average
• +0.5 at this ground — averages 1.5 there (4 gm)

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 16: 4 — far outside his usual range; kept in the average, not smoothed away.