If you have confidence in your numbers (most players know how to make a solid line) and a game opens in your favor, play it. If you wait, and don't get a good number, you have no one to blame but yourself.
Ex. ST. LOUIS /CUBS OPENED 9 under -20. I grabbed the 9 under as early as I could. When you war you are taking a chance, sometimes you get a better line, in this case the 9 went to 8 1/2 then to 8 and at game time I saw 8 all over. In this case I won because I played early. UNDER 9 and won.