• 6.1 baseline — 0.6 × season 6.1 (16 gm) + 0.4 × last 10 6.2
• +0.1 opponent leak — they concede 157/game vs a 155.4 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.