• 4.5 baseline — 0.6 × season 4.8 (6 gm) + 0.4 × last 10 4.1
• −0.5 opponent leak — they concede 82.5/game vs a 93.4 league average
• vs them: averages 8.0 over 1 game — 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 4: 9 — far outside his usual range; kept in the average, not smoothed away.