• 26.4 baseline — 0.6 × season 25.3 (16 gm) + 0.4 × last 10 28.2
• −2.3 opponent leak — they concede 1543/game vs a 1687.8 league average
• +12.3 at this ground — averages 38.8 there (26 gm)
• vs them: averages 84.5 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 22: 80 — far outside his usual range; kept in the average, not smoothed away.