I added that disclaimer at some authors' suggestion. However,

• AnnoCPAN does send an email notification to authors whenever someone posts a note to their modules (it's opt-in after the first email).
• If an author changes the master documentation in response to a note, the note won't show up when viewing the documentation for the new version of the module (It usually guesses automatically when it shouldn't be shown, but when it doesn't guess right the note can be hidden manually. If I've missed one please let me know.)