I have never used tags across any of my sites for the past 3 years due to the impression of causing on-page duplicate content. Well today has been a long day for me, i spent a whole damn day spying on most of my competitors and i noticed that almost all of them use quite an amount of tags on their most of their pages. They outperform my main site btw. Also did a small research and notice almost all huge authority sites use quite an amount of tags on every single posts. So what do you think guys? what is real experience with this?