• 6.9 baseline — 0.6 × season 7.0 (6 gm) + 0.4 × last 10 6.8
• +0.9 opponent leak — they concede 106.2/game vs a 93.4 league average
• −1.0 at this ground — averages 5.9 there (10 gm)
• vs them: averages 5.3 over 10 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. Round 7: 11 — far outside his usual range; kept in the average, not smoothed away.