• 1.1 baseline — 0.6 × season 1.3 (12 gm) + 0.4 × last 10 0.8
• +0.1 opponent leak — they concede 25.6/game vs a 23.6 league average
• at this ground: too thin to count (2 gm) — shown, adds nothing
• −0.7 wet forecast — averages 0.4 in the wet (9 gm)
• vs them: averages 0.8 over 5 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 2: 8 — far outside his usual range; kept in the average, not smoothed away.