• 0.2 baseline — his last 10 games; only 1 this season, too few to blend
• +0.0 opponent leak — they concede 38.4/game vs a 35.7 league average
• +1.7 at this ground — averages 1.9 there (34 gm)
• vs them: averages 0.3 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.