• 0.3 baseline — 0.6 × season 0.3 (19 gm) + 0.4 × last 10 0.3
• −0.0 opponent leak — they concede 9.2/game vs a 9.4 league average
• at this ground: too thin to count (2 gm) — shown, adds nothing
• −0.2 wet forecast — averages 0.1 in the wet (9 gm)
• vs them: averages 0.0 over 4 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.