I don't agree with this idea. A corner time such it is may be an independent punishment. To stand in a corner of the class (sometimes with the arm up) was a common punishment when I was in the primary school. And it was shameful for a pupil to be send to the corner of the class.
As for the spanking, I think that a corporal punishment has to consist in the infliction of pain and humiliating in the same time. The pain must be a true one, but the humiliating may be an extra useful to prevent the culprit to repeat his mistake. That is why there are some rituals - the culprit had to bring himself the implement, the waiting before the spanking, the position, etc. - destined to grow the humiliating and to make from a spanking a memorable event. Among them, I think that the corner time is an effective one.