• 0.5 baseline — 0.6 × season 0.5 (8 gm) + 0.4 × last 10 0.4
• +0.1 opponent leak — they concede 10.8/game vs a 9.4 league average
• at this ground: too thin to count (2 gm) — shown, adds nothing
• vs them: averages 0.0 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 13: 2 — far outside his usual range; kept in the average, not smoothed away.