• 11.7 baseline — 0.6 × season 6.0 (5 gm) + 0.4 × last 10 20.2
• +0.1 opponent leak — they concede 548.9/game vs a 544.2 league average
• at this ground: too thin to count (1 gm) — shown, adds nothing
• vs them: averages 22.0 over 2 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 18: 77 — far outside his usual range; kept in the average, not smoothed away.