• 6.5 baseline — 0.6 × season 6.1 (18 gm) + 0.4 × last 10 7.2
• +0.4 opponent leak — they concede 164.6/game vs a 155.4 league average
• −1.5 at this ground — averages 5.1 there (27 gm)
• vs them: averages 5.0 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.