Hello, I did read Diana's book, great read.
I did fight cyanobacteria since I did began having planted aquariums 2 years ago. In fact, I had cyano in all my setups, having serious invasions at time.
I trust allelopathy works over time. I remember Diana mentionning "mild allelopathy" in his book.
I my case I do complete fertilisation through the water column and it's helps the plants a lot. At one point plants and cyano grow quite well together at the same time. I remove the cyano regularly, it's easy to remove by siphonning or with a fish net. Over time the cyano disappears by itself. In my last setup, low light, with ferts, it took 4 months to disappear. I had fast growing plants like limnophila sessiflora, ceratopteris thalictroides, & egeria densa.
I have moved my tank recently, it's in water since august 18th. I have CaribSea Sunset gold sand mixed with seachem flourite. This time I did add only 1,5L of Miracle Gro potting mix below the substrate. It did give a serious boost to the plants (limnophila sessiflora grows agressively, i did already begin to trim it regularly a week ago, if I do not it will cut the light of my bacopas monnieri, which grows slower).
I have some cyano too, but scarse. Probably that cyano will expand since the tank is young, but for me it is the way of things, it's normal in the beginning.
I did never use blackouts, or anti-algae chemicals. I believe well maintained plants will keep algae in check but you need patience, it normally takes many months.
Michel, hope it helps.