• 1.8 baseline — 0.6 × season 2.1 (17 gm) + 0.4 × last 10 1.4
• −0.0 opponent leak — they concede 35.4/game vs a 35.7 league average
• +1.5 at this ground — averages 3.3 there (32 gm)
• vs them: averages 3.4 over 8 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 5: 7 — far outside his usual range; kept in the average, not smoothed away.