• 25.5 baseline — 0.6 × season 24.8 (20 gm) + 0.4 × last 10 26.5
• +1.2 opponent leak — they concede 386.5/game vs a 369 league average
• −1.1 at this ground — averages 24.3 there (6 gm)
• vs them: averages 25.0 over 1 game — 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.