• 2.5 baseline — 0.6 × season 2.4 (20 gm) + 0.4 × last 10 2.6
• +0.3 opponent leak — they concede 64.2/game vs a 56.6 league average
• +0.9 at this ground — averages 3.3 there (86 gm)
• vs them: averages 4.1 over 13 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 11: 6 — far outside his usual range; kept in the average, not smoothed away.