1) The document discusses using Plone and Volto as a backend with GatsbyJS as a frontend Jamstack project. It describes using Plone for content authoring and hierarchical permissions, and GatsbyJS for a fast responsive frontend.
2) It provides an example of a University of Jyväskylä study guide site built with these technologies, containing 6000 pages in two languages. Plone was used for no-code content customizations and Volto for auto-complete widgets.
3) While GatsbyJS provided many benefits, the author notes it requires practice to fully utilize and overcome challenges like long build times and memory usage during builds. Using Volto in Gatsby