I'm not sure that i agree on ID effecting offensive rebounding.
As far as i've been able to tell, it's purely a rebounding based thing and the rebounding of your team mates compared to the opposition. Obviously a defensive tactic can effect this with a 3-2 zone more likely to give away more offensive rebounds and a 2-3 zone more likely to stop offensive rebounds and stamina will play a part as the game goes on as well.
Don't forget, rebounding isn't just getting the ball yourself, it's also boxing out your man too.