• 2.2 baseline — his last 10 games; only 3 this season, too few to blend
• −0.3 opponent leak — they concede 10.3/game vs a 12.2 league average
• at this ground: too thin to count (1 gm) — shown, adds nothing
• −0.4 wet forecast — averages 1.8 in the wet (6 gm)
• vs them: averages 1.7 over 7 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 21: 5 — far outside his usual range; kept in the average, not smoothed away.