Well, I built a theming engine that utilized LESS in combination with a whole host of other stuff. It became a big problem there, but that's not really a use-ca

Well, I built a theming engine that utilized LESS in combination with a whole host of other stuff. It became a big problem there, but that's not really a use-case that is applicable to most. For more common issues, the way LESS does guarded mixins was super annoying, the breaking changes in minor version release, etc.