Is this document assembly? Yes...and no. "Yes" in that these methods are the "tip of the tip" of the iceberg, but "No" in that these approaches and systems do not reflect even 1% of the functionality and profit available via document assembly avenues.
Now that's not to say that you buy some document assembly software and install it, tap a few keystrokes and have a licence to print money - document assembly is not "plug and play" style software such as Outlook or Microsoft Word. A document assembly system should reflect your intellectual property and drafting styles, with your firm's specific needs addressed and rarely will it be purchasable "off the shelf".
Nor is it to say that you will have to spend months learning a new programming language and syntax only to obtain mediocre results.
Document assembly is a very simple concept that can take your firm to higher levels of productivity without increasing existing staffing levels.