• 2.6 baseline — 0.6 × season 2.8 (5 gm) + 0.4 × last 10 2.4
• +0.4 opponent leak — they concede 64.3/game vs a 56.6 league average
• at this ground: too thin to count (1 gm) — shown, adds nothing
• −1.2 wet forecast — averages 1.4 in the wet (7 gm)
• vs them: averages 4.0 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.