• 24.7 baseline — 0.6 × season 24.6 (20 gm) + 0.4 × last 10 25.0
• +1.2 opponent leak — they concede 386.2/game vs a 369 league average
• −3.2 at this ground — averages 21.5 there (32 gm)
• vs them: averages 18.0 over 3 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.