I tried the lights out for 3 days approach.. after the cyano was mostly gone. I know my tank has a bit to go to mature, and to me the lights out approach can be a band-aid for an issue that needs to be fixed. Thats the only reason I have tried it once and started looking more towards nutrients. How much nutrients were going into the tank, how much were being used, and how much were left to wreak havoc lol.
Part of my issue at that time was husbandry skills. I have a shallow sandbed and found out I needed to be cleaning the sand better than what I was. Now that I take small sections once-twice a week and stir/clean it.. most of that problem has diminished. Still have some cyano but nothing like it was.