• 0.7 baseline — 0.6 × season 0.7 (20 gm) + 0.4 × last 10 0.7
• +0.0 opponent leak — they concede 13.4/game vs a 12.8 league average
• −0.1 at this ground — averages 0.6 there (19 gm)

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.