I am a criminal defense lawyer. I have a lot of forms and boilerplate pleadings I need to use as rough drafts. So I have basic information about a case that needs to go into a number of different documents at different times. For that, I use Mail Merge. It gives me the rough draft of my document with the client and case information filled in. I make some changes and file with the court or send to opposing counsel. That is a different method than what you are looking at.