I wish I could agree, Cyano can grow anywhere and everywhere, yes having a bare bottom tank can lessen the amount of mutrients/waste in a tank, but cyano doesn't care about all that, it feeds on nutrients and light, I've seen it first hand.
I also have used Chemi-clean with great success, but it should be considered part of the solution, ie water changes, water flow, lowered feeding, phosphate removal are also very important to keep it at bay.