If I told you tactic X produced a 150% uplift in conversion rate for one of my landing pages, would you go and test it as well? I hope not ;) You'd need a lot more details for it to make sense.
The tactics are meant to serve as an inspiration. You can never blindly apply a random tactic you find on the Internet. It always has to be adjusted to your specific use case. And ideally, backed up by a reasonable hypothesis and data.