• 10.9 baseline — 0.6 × season 10.5 (17 gm) + 0.4 × last 10 11.6
• −0.7 opponent leak — they concede 200.8/game vs a 213.6 league average
• −3.4 at this ground — averages 7.5 there (11 gm)
• vs them: averages 9.1 over 12 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.