• 0.8 baseline — 0.6 × season 0.6 (5 gm) + 0.4 × last 10 1.1
• +0.1 opponent leak — they concede 64.3/game vs a 56.6 league average
• +0.7 at this ground — averages 1.5 there (8 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.