First, it is stated:

"The markup that generates the presentation is limited to be purely presentational: it may never run script (including inline event hanlders) and it cannot be editable."


Then, it is stated: 

"Similarly, if script changes the content of the template later, this doesn't have any effect on the decorator, just like setting the textContent of a <script> element doesn't cause the script to execute again."

So I am just confused how both of them apply. I am most likely misunderstanding something.