It allows you to decide who wins for key press in text areas, which I hope would minimize wrestling with google docs

Here's the relevant features which you can control on a URL basis:

Textarea: When enabled, multi-line text editors (HTML textarea elements) are also protected by the website options "⌘-key shortcuts", "Cut, copy, and paste", and "Text selection". By default, only single-line editors (HTML input elements) are protected, because multi-line editors don't usually prevent copy and paste, and a lot of websites have special multi-line "rich text" editors with highly customized editing that can break with the textarea feature enabled. However, you may need to enable this feature on certain websites if they disable copy and paste.

All key presses: When enabled, stops websites from hijacking key presses on the page. This feature cannot be enabled with the Default options for all websites, because it would cause breakages on too many sites. It usually shouldn't be necessary, but in some rare cases a website will go to extreme lengths to interfere with your typing. (Note: textareas are not covered by "All key presses" unless the "Textarea" option is also enabled.)