Let's say they're playing against each other. You still have a possession unaccounted for. The first team missed after all after scoring in a secondary possession.To quote Roy:
You only provided the second team with one possession when they should've had two just the same.
A: Celtics have ball. Miss shot. Lakers get ball. (Outcome unknown). Celtics get ball, make shot. Lakers get ball.
B: Celtics have ball. Miss shot. Offensive rebound. Make shot. Lakers get ball
In this particular case, we're trying to capture the offensive efficiency of the Celtics. Laker possessions should be all but irrelevant.
I don't see how you can not find it relevant. And I don't think those are good examples because we're not comparing the same amount of possessions.
Lakers miss shot. Celtics get ball and score. Lakers make shot. Celtics miss shot, offensive rebound, and score.
I combined the two scenarios above into one possibility of in-game situation/
In example C, Celtics when 2/3 for 4 points in two possessions, 2 PPP
Lakers miss shot. Celtics get ball and miss. Lakers make shot. Celtics miss shot, offensive rebound, and score.
In example D, Celtics went 1/3 for 2 points in two possessions, 1 PPP (basically the same as scenario A, but with an additional miss).
I hope this illustrates the importance of including the possession that is missing from the scenarios that have been presented to this point.