• 4.6 baseline — his last 9 games; only 1 this season, too few to blend
• +0.3 opponent leak — they concede 225.5/game vs a 213.6 league average
• −2.1 at this ground — averages 2.5 there (4 gm)

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.