• 10.6 baseline — 0.6 × season 10.2 (15 gm) + 0.4 × last 10 11.1
• −0.1 opponent leak — they concede 363.9/game vs a 369 league average
• −0.9 at this ground — averages 9.6 there (8 gm)
• wet forecast: too thin to count (2 gm) — shown, adds nothing
• vs them: averages 9.5 over 4 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.