• 23.6 baseline — 0.6 × season 22.8 (16 gm) + 0.4 × last 10 24.8
• +1.1 opponent leak — they concede 386.5/game vs a 369 league average
• +0.5 at this ground — averages 24.1 there (38 gm)
• vs them: averages 20.1 over 7 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 18: 9 — far outside his usual range; kept in the average, not smoothed away.