GL,
The blocking is not something that [...has to be done...]. Objectional posts can be deleted. Objectionable posts can be reviewed by a group and sent back to the poster before it is left on the board to be modified to meet the guidlines of the forum so that it can be posted. Objectional posts can be penalized by other means than blocking the poster in toto, such as limiting the number of posts for so many days if a post does not meet the guidlines of the forum. And there are other good and just alternatives to ostracism.
Lou