• 25.4 baseline — 0.6 × season 25.3 (12 gm) + 0.4 × last 10 25.4
• −0.3 opponent leak — they concede 364.1/game vs a 369 league average
• −6.8 at this ground — averages 18.6 there (9 gm)
• vs them: averages 14.0 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.