The "imminent change of possession" rule used to be that you could't grant a team's TO request if they had a count against 'em and had used up 80% of the count.In other words if you hit 4 on a 5-second closely guarded count or throw-in count,or 8 on a 10-second backcourt count,you wouldn't grant a TO request.You just kept counting until there was a violation,or the team managed to avoid the violation(rare).When the rule first came in,I once asked a renowned rules interpreter what 80% of a 3-second count was.He thought about it for a minute,and then called me an a$$hole.