Key Findings
Blind betting is structurally negative after vig: the major baseline markets sit below the -110 break-even rate. The useful layer is not "favorite vs underdog" by itself; it is price plus context.
Weather is the strongest historical signal in this build. Wind at 10+ mph and especially 15+ mph has produced the cleanest under profile, with a large enough sample to deserve pre-game monitoring.
Underdog patterns are more nuanced. Division dogs and large dogs can reduce favorite tax, but most broad ATS angles are near break even before line-shopping and closing-line value.
Recent Season Advice
2020 rewarded underdog pricing, 2021-2023 rewarded disciplined under betting, 2024 flipped toward overs, and 2025 offered no clean broad edge. The lesson is to avoid marrying one angle: keep the long-term wind-under signal, but let each season's market regime decide whether the bet is worth paying for.
Wager Rules
- Require at least 250 historical bets or a clear domain reason for a smaller sample.
- Demand positive ROI after -110 vig, not only a win rate above 50%.
- Confirm the current matchup still matches the filter: QB status, weather, rest, venue, and line.
- Track closing-line value; discard angles that win historically but lose price discipline.
- Cap exposure per wager and avoid chasing; historical edges can regress quickly.
Data Notes
Source data comes from nflverse/nfldata game history. Spread lines are evaluated from the home-team perspective: home ATS margin = result minus spread_line. Totals use scored points minus total_line.