• 15.2 baseline — 0.6 × season 13.2 (5 gm) + 0.4 × last 10 18.3
• +0.9 opponent leak — they concede 365.4/game vs a 344.7 league average
• +4.1 at this ground — averages 19.4 there (11 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 3: 0 — far outside his usual range; kept in the average, not smoothed away.