screen options – discussion and comments

I would like someone who knows how this stuff works to review this and see if I have it right. If so maybe this could eventually evolve into documentation on the use of comments/discussion (rather than just a forum post) . I spent several hours trying to figure out how comments/discussion works, and having better documentation on this subject would have saved me much of that time. This applies to ver. 3.2.1

The help document at the Settings Discussion Subpanel – Settings Discussion Screen starts out with this sentence: “The Settings Discussion Screen allows you to set the options concerning comments (also called discussion).” This is only loosely accurate. In reality a series of comments is the content of a discussion.

To turn off discussion for a single page (turning off discussion for all pages is in the Settings: Discussion section), and thereby the ability to post comments, go to Page: Pages, and edit the page for which you wish to turn of discussion and comments. Click on the Screen Options button near the top right of the screen. This will open the options dialogue. Under “Show On Screen” in the box that opens, click on the check box next to discussion. This will open a box under the edit box. In this box uncheck the Allow comments checkbox. go back to the Screen Options box and uncheck Discussion. Both boxes must be unchecked. Close the “Screen Options” box. Update the page.

NOTE that this only turns off future comments and discussion. It does not turn off comments and discussion that were created before this time, and does not stop additional comments on already existing posts. To stop comments on already existing posts, comments should be turned off for each post in a manner similar to the above, but starting at Posts instead of at Pages.

Question: Is there a tool to turn off comments on all previous posts? Is there a tool to run off all reference to posts (not even display “Comments Off” – as thought the capability did not exist)?

thanks