I had a thought (just one. i try not to over-exert) today. Because they are set in order to entice 50% of gamblers to wager on either side of the game, the spreads are tied pretty loosely to likelihood of victory, more closely to public opinion, and most closely to the opinions (and whimsy) of gamblers.
Much like the stock market, I'm thinking that as underrated teams out-perform the spread week in and week out, gamblers jump on the bandwagon in increasing numbers, thus forcing an over-correction and a spread that they will not be able to cover. This should also happen in reverse as losing teams are bet against, giving them a spread they can cover.
I will call this my Wave Theory. As of this morning it is just a bit of half thought-out logic, but I am going to put some research into comparing teams' records against the spread and see if their is any patterns to teams that consistenty win or lose against the spread. Stay tuned.
Coming up... Mad Capping this week's game.