• 42.4 baseline — 0.6 × season 41.2 (20 gm) + 0.4 × last 10 44.1
• +1.2 opponent leak — they concede 559.8/game vs a 544.6 league average
• −1.0 at this ground — averages 41.4 there (46 gm)
• +3.1 wet forecast — averages 45.5 in the wet (10 gm)
• vs them: averages 40.2 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 22: 72 — far outside his usual range; kept in the average, not smoothed away.