I understand by the answers I get, that I haven't been crystal clear in the original question.
I should have said "recipients" instead of "reader".
The idea is that I have an original (a template) with 20 chapters. I want to be able to easily adjust this information and send only some of it to some recipients and some information to other recipients. Exchange the term "reader no 1" with "recipient Group 1" in the original post and you might get the idea. To clarify - the recipients do not need the template, as they will not do any updates.
I do not have any sensitive information I want to hide, it is just a matter of showing only the information that the recipient is interested in reading, as it is a very large document originally.

Do you still recommend Autotext and IF fields?

I am no stranger to macros, although I have only worked with them in Excel so far. But, an "easy" way is better as there are other - and less technical - people who will update the original template. That said, I would be interested in any macro example that shows how this can be done :-)