• 16.6 baseline — 0.6 × season 16.1 (15 gm) + 0.4 × last 10 17.5
• −0.1 opponent leak — they concede 367.1/game vs a 369 league average
• −1.6 at this ground — averages 15 there (6 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.