I love it when I get the low-res summary word-for-word.

GO NOLES!

It is "THE ONLY," so it belongs to group 1 which introduces a sufficient indicator.

I believe you use what ever works for you. However, more likely than not, you should use the J.Y. method because of its simplicity. The more advanced an argument, the more difficult it might be to show negation when graphing in future lessons.