I have never really broken all that down that much. But I would think it would be less than a nickle actually. But because that is pretty much the lowest split a book can make that is what they would probably use if they offered it. I do have push results at certain spreads, but I do nat have results where the lines were a half point off the actual score.
In the NBA there are far more variables in scoring than in football, as we all know. But with totals it is even more defined. In a blow out the total might not even come into play at all. But in a close game with free throws the total can be put in jeopardy even if it isn't even close until late. Not only with OT, but with a team that gets behind by 3 to 5 points and fouls every time the other team gets the ball. Especially if you have an under. How many times have we had under 185, the score is 90-89 with 20 seconds left, a guy makes a shot, and a few free throws, and an uncontested lay up later we are a loser.
I don't bet the NBA regular season anymore. But I remember that there were far more 'bad' beats in the NBA than in all the other spread based sports combined. That is why I don't bet it. It is nearly impossible to handicap it and win.
Like the old cliche says, just watch the last minute to see the game. Because for the most part that is when a large majority of the games are decided. Even with the Lakers last night, they had like a 33 point lead at one point, but if you flipped it on with a couple minutes left you would think they were hanging on tooth and nail (which they were at that point actually).
NBA Hoops is a totally different animal, and I am not too proud to say that I can't beat it. That is why I don't bet it. I just make more wagers in the NCAA where there can be exploitation.