This is pretty exciting! In this case, users will retain an 'escape hatch' in the sense that they'll be free to descend from whatever higher-level configuration

This is pretty exciting! In this case, users will retain an 'escape hatch' in the sense that they'll be free to descend from whatever higher-level configuration options a module author wants to offer (which could set multiple settings, or generate settings based on other settings) and use all the configuration primitives offered by the underlying software being configured. We just won't have to manage it as a big, dumb string anymore. :D I suppose this could still be annoying for someone who really just wants to copy/paste, though.