The process you defined with GitHub pull requests is correct, for cases where the documentation is enhanced to support a new feature in the code.  

I wanted to add Disqus as a mechanism for anyone reading the documentation to ask questions about the documentation, add more information from real-world experiences, or report fixes to the documentation.  E.g., suggest that something isn't clear, isn't addressed, is incorrect or to provide additional information.

Similar, for example, to the "User Contributed Notes" section of the PHP documentation (I've picked some random pages here - scroll towards the bottom to find the User Contributed Notes):

http://php.net/manual/en/language.operators.string.php

http://php.net/manual/en/language.oop5.traits.php

MySQL has something similar:

http://dev.mysql.com/doc/refman/5.5/en/create-database.html

http://dev.mysql.com/doc/refman/5.5/en/drop-index.html