• 5.0 baseline — 0.6 × season 4.8 (20 gm) + 0.4 × last 10 5.2
• −0.6 opponent leak — they concede 82.5/game vs a 93.4 league average
• −2.0 at this ground — averages 3 there (4 gm)
• −1.3 wet forecast — averages 3.7 in the wet (19 gm)
• vs them: averages 3.2 over 9 games — evidence, never summed

Most signals here point under while you're on the over — worth reading the working above before you commit.

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 11: 12 — far outside his usual range; kept in the average, not smoothed away.