• 51.7 baseline — 0.6 × season 50.9 (20 gm) + 0.4 × last 10 53.0
• +1.4 opponent leak — they concede 559.8/game vs a 544.6 league average
• at this ground: too thin to count (3 gm) — shown, adds nothing
• vs them: averages 51.8 over 9 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 9: 101 — far outside his usual range; kept in the average, not smoothed away.