It all depends on your motivation, but what I prefer to do is think about the reader. Imagine there’s some post and someone makes a comment and I know that the comment is wrong or misleading. So I might decide to reply. And my comment is there to help readers not be deceived by the previous comment.

Therefore, I don’t need to deal with any sub comments and I don’t need to keep following that thread. The most important thing was to have a rebuttal to the primary claim that was made and I already wrote that so my work is done. I find this to be an okay use of time, at least some of the time, because a lot of times the commenter that I’m replying to is someone that I just can’t reach. They might have some immovable position on a political issue or they could be religious or they could be argumentative or trolling. And I could go back and forth with them several times, but really nobody else would read our thread, so it would be a waste of time.

Of course that’s only one approach and it really depends on the types of comments and issues that you’re concerned with. But it’s one way to reduce stress and save you time.