Spacing it out over time, one a week, will also force the press to focus on the individual being stripped of his clearance and enable his role in the conspiracy to be written about. Doing 7-8 people at once allows the press to gloss over them as a group and put the focus on the act and not the reason why for that person.
Don’t you think that getting the clearances cancelled ASAP should take precedence over any political advantage that might be gained by “dribbling” them out as you suggest?