• 11.6 baseline — his last 10 games; only 3 this season, too few to blend
• −1.1 opponent leak — they concede 494.6/game vs a 544.2 league average
• −0.6 at this ground — averages 11 there (54 gm)
• vs them: averages 8.3 over 6 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.