The problem with the "bad line" rule is that while the top books tend to be fair about it, some smaller books will use that rule very liberally to reverse action on bets they don't want. The worst offenders are the ones who put up a line, the line steams, and they let their line sit there, and they try to void it as an "obvious bad line" even though the line was right in line with the market at the time.
I've had shitty books void bets at +135 when major books like the Greek, CRIS etc had +110/-130, which is not at all far enough off to the considered a "bad line." I've also had them void bets on props where it is often not clear what constitutes a bad line and what doesn't. For example, before the Broncos/Patriots game, the Broncos were hugely favored to punt first on lots the books even though they were only a small underdog for the game (I got some Pats -2.5 -115), and I read that the reason for this was because New England likes to defer the kickoff, making the Broncos favored to get the ball first and hence punt first. On the surface Denver -180 to punt first looks like a bad line but not if they are heavily favored to get the ball first rather than 50/50.
I've had shitty books void bets at +135 when major books like the Greek, CRIS etc had +110/-130, which is not at all far enough off to the considered a "bad line." I've also had them void bets on props where it is often not clear what constitutes a bad line and what doesn't. For example, before the Broncos/Patriots game, the Broncos were hugely favored to punt first on lots the books even though they were only a small underdog for the game (I got some Pats -2.5 -115), and I read that the reason for this was because New England likes to defer the kickoff, making the Broncos favored to get the ball first and hence punt first. On the surface Denver -180 to punt first looks like a bad line but not if they are heavily favored to get the ball first rather than 50/50.
