• 3.7 baseline — 0.6 × season 3.2 (19 gm) + 0.4 × last 10 4.4
• +0.5 opponent leak — they concede 27.1/game vs a 23.7 league average
• −1.7 at this ground — averages 2 there (8 gm)
• vs them: averages 2.3 over 6 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 22: 14 — far outside his usual range; kept in the average, not smoothed away.