• 2.1 baseline — 0.6 × season 2.4 (5 gm) + 0.4 × last 9 1.7
• +0.3 opponent leak — they concede 64.3/game vs a 56.6 league average
• −0.3 at this ground — averages 1.8 there (6 gm)
• vs them: averages 0.0 over 1 game — 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.