I know exactly what you are talking about ck. I have noticed that quite a few lines are posted and then moved off key numbers, those games seem to be covering.
NFL examples today
Chi -10 then moved to Chi 9.5, could be read both ways but chi covers
N0 -7 then goes to -7.5, seems like that is baiting jets bettors, NO covers
Den +3 then goes to Den +2, again looks like they are trying to draw in cowboy backs, Den covers
I personally see the line moving on and off of key numbers than I have ever before