• 16.8 baseline — 0.6 × season 16.8 (19 gm) + 0.4 × last 10 16.8
• −1.2 opponent leak — they concede 343.2/game vs a 369 league average
• −1.0 at this ground — averages 15.8 there (13 gm)
• vs them: averages 14.6 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 1: 26 — far outside his usual range; kept in the average, not smoothed away. Round 11: 26 — far outside his usual range; kept in the average, not smoothed away.