And I recently learned that it will open the embedded language in its own editor pane (ala editing code in org mode, if that means anything) and can be a less distracting way to edit without the mental encode/decode cycle

It may have been implied by the "it autocompletes" statement, but it runs analysis on that code, too, catching bad practices such as logic errors, common mistakes, and unused code (where applicable)

One can influence its embedded language detection via `language=RegExp` (or whatever the language id is) while inside a comment right above the embedded language literal: https://github.com/JetBrains/intellij-community/blob/idea/20...