Doesn't work for me in Sierra. The only SIMBL plug-in I was using before upgrading to macOS 10.12 was colorfulsidebar in Mavericks. But even with System Integrity Protection disabled the plug-in no longer affects Finder windows. I uninstalled SIMBL and reinstalled version 0.9.9. MySIMBL shows SIMBL and the colorfulsidebar plug-in enabled, but they don't work. If they had, I would consider running with SIP disabled, but since they don't, I re-eanbled it.
In the meantime, I have a feature recommendation. It would be helpful if there were a select all feature in the blacklist window. This would make it easier to enable it in selected applications so that the "run in" button would apply only to those apps which, it seems to me, would be a lot safer.