My impression was that they were trying to go for a more "middle ground" approach to things that made it easy to convert old existing templates (written in less

My impression was that they were trying to go for a more "middle ground" approach to things that made it easy to convert old existing templates (written in less safe dialects like jQuery templates). Since the legacy code allows you to have inline URLs that you put things in you can't force the users to refactor things to generate all the URLs outside the templates.