When participants sign up, they are allowed to make Comments. An organizer can prevent other participants from seeing the comments made by others. Here is how you suppress/hide comments:
If you are creating a new signup, it will be on the first page:
If your SignUp is already set up and you wish to hide comments, go to My SignUps on your Dashboard. Click on the SignUp Title, then click on the Details tab:
Scroll to this option and change: