• 2.6 baseline — 0.6 × season 2.8 (4 gm) + 0.4 × last 5 2.4
• −0.1 opponent leak — they concede 53.5/game vs a 56.6 league average

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.