• 1.1 baseline — 0.6 × season 1.2 (17 gm) + 0.4 × last 10 0.9
• +0.2 opponent leak — they concede 14.9/game vs a 12.8 league average
• −0.2 at this ground — averages 0.9 there (8 gm)
• vs them: averages 1.4 over 5 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.