The software provides a simple way to include variables in technical documentation. It also integrates with an R engine for editing R Markdown files, which can also use variables sourced from an external YAML file. (Editing XML documents that have stylesheets is possible, too.)
My authoring workflow involves Scrivenvar, Markdown, pandoc, knitr, and ConTeXt. As Markdown separates content from presentation, I prefer ConTeXt to LaTeX for the same reason.