• 3.6 baseline — 0.6 × season 3.6 (18 gm) + 0.4 × last 10 3.5
• +0.2 opponent leak — they concede 60.4/game vs a 56.6 league average
• −0.3 at this ground — averages 3.3 there (10 gm)
• vs them: averages 2.0 over 3 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.