Actually Flower, not to be mean, but the advise you are giving here is horrible. Just plain horrible. Though I know I've heard it given many times. It goes along with the idea that ich is a part of life and that all tanks have it.
The fact is it is not just a part of life. My tank is ich free and my fish have great immune systems. But they have the great immune systems in ADDITION to being parasite free. This is like having your pet dogs ( that you loved so dearly) bed laying right next to a rattlesnake den and you only see the snake "every now and then", plus you've got some anti venom if in case it does bite it. Wouldn't you rather kill the snake? Even if you had to not let your dog near its bed for 6 weeks? Poor method I'm sorry.
It's not new thinking with the one year thing...Research, then you can give advise. Giving bad advise as if it's good advise creates horrible advise.
Now there are many methods to deal with ich. All of them attach the parasite at a specific time in it's life. One simply separates the fish from the parasite at the optimum moment and interrupts the lifespan. Finding that particular moment is difficult at best. Hyposalinity kills the parasite when looking for a host during the free swimming stage. Copper kills it at this time also. The transfer method separates the fish from the parasite at the time it leaves the fish. Vacuuming and cleaning surfaces daily or twice daily is another method with very limited results. It can though limit the impact of a bad outbreak. Increasing the fishes slime coat causes the parasite to not be able to attach very well. This is the process basically involved with the increased immune system. Many of the snake oils essentially do this by irritating the fish, thus stimulating the slime coat.
I forget the who's and the whats regarding 11 months with no new DNA, But there was a study done on ick years ago where they used tank raised fish and one strand of ick. After 11 months the "culture" of ick became no longer viable. The researches could not keep a culture live beyond this time frame. Thus the conclusion was drawn that the parasite needs some variance in DNA over the 11 mo. or it will perish. Adding any new fish DNA to the tank would reset this. Allowing for another 11 mo. of viable culture. one could draw the conclusion that if you can go for 11 months or preferably 1 year without adding any new fish, ANY. Then you will likely have cured the tank of it. The question is, can you do that?
Now this is not a proven science so much as who could actually prove it works in the aquarists tank. But those are the results the repetitively found. I would not recommend this as a "treatment" it is not. My dogs wont lie next to the snake den for 12 mo.
