• 5.3 baseline — his last 10 games; only 1 this season, too few to blend
• −0.0 opponent leak — they concede 35.6/game vs a 35.7 league average
• −1.3 at this ground — averages 4 there (4 gm)
• vs them: averages 7.0 over 2 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.