I meant the user name, not any other information the moderators may have.

The second paragraph is intended to follow from the first because:

• I expect posting information about mass-downvoting to reduce its effectiveness, because
  • people will feel less bothered by getting lots of downvotes if they know they come from a low-quality mass-downvoter
  • readers who know that A has been mass-downvoting B will be aware of that when looking at B's comments and may discount downvotes on them accordingly.
• I expect posting information about mass-downvoting to reduce its attractiveness, because
  • prospective mass-downvoters will anticipate getting exposed, with likely consequences for their own reputation (and in particular their ability to amass the karma they need for the mass-downvoting).
• I expect the promise of future exposure to inhibit mass-downvoting by a further mechanism:
  • prospective mass-downvoters will fear that they may get not only exposed but banned, which would (at least) be an inconvenience.