The NBA preseason is just too long. In reality it is only 2 weeks of our time, but the Celtics played 7 games in that time, and used some to rest starters and certain players. Yes, it's useful to try to sift through who is in and who is out at the bottom of your bench. Sure, it can help find out who the fringe of your starting lineup or rotation will be. But you could find those things out in 4 games rather than 7 or 8. Brad Stevens agrees.
BS on preseason: " I think that you can probably figure out what you need to figure out with less (gms).