You are correct about that. Players sitting out, saving themselves for playoffs. It happens all the time. Example Det/Dal the line only 13 1/2 told you was going to cover even though you knew the big guns would not be playing. You could only use games that mean something. Tomorrow 1 of the games that has a lot of meaning to both teams is Min/Phoenix. Both of these teams have something to play for.
Yes i think it makes a lot of sense.
Right now PHX/MIN is -4 217.5
The model has MIN winning by 10 points, 118-108, but this doesnt means that MIN is the pick, in fact, there is no pick on this game. Right now i would fade it, take PHX +4.
But as you mentioned, the model doesnt takes into account playoff implications and the feeling that the season could come to and end to some teams. Also, all players play differently when the pressure is on.