• 17.5 baseline — 0.6 × season 17.5 (19 gm) + 0.4 × last 10 17.6
• +0.4 opponent leak — they concede 378.4/game vs a 369 league average
• −0.5 at this ground — averages 17 there (23 gm)
• vs them: averages 16.0 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. Round 6: 5 — far outside his usual range; kept in the average, not smoothed away.