I believe the reason for bringing in the idea of there being no typos in the entire book is to show how you aren't able to reason well without some change in yo

I believe the reason for bringing in the idea of there being no typos in the entire book is to show how you aren't able to reason well without some change in your approach. Of course, the comments here suggest that it just makes the whole concept confusing to an audience who should either already know about confidence intervals or be well prepared to learn about them.