• 36.9 baseline — his last 10 games; only 1 this season, too few to blend
• −6.7 opponent leak — they concede 28.9/game vs a 35.3 league average
• −5.6 at this ground — averages 31.3 there (6 gm)
• vs them: averages 28.3 over 8 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.