Enforcing Strict Model-View Separation in Template Engines by Terrance Parr
The short version is that JSP makes XHTML VIRTUALLY IMPOSSIBLE to validate in it’s fragmented form, which would be much, much, faster than compiling it and then running an html test on a server version to check it’s validity. “Fail fast” is the phrase du jour with CI/CD and JSP prevents this, as well as creating a HORRIBLE HORRIBLE mess of crappy crappy code.
So in short, never use JSP, or Faces, or any of those other ridiculous technologies. The only thing that prevents you using String template is unfounded fear. The pain you save your developers is worth it. Trust me.