In my very small limited experience, I've found that the best way to get rid of thrush is to build the back of the hoof so the horse is landing heel first......and then get that horse moving around a lot. Thrush just seems to go away once the horse has consistent heel first landings and is moving many miles per week. I should also say that this is my experience with a barefoot hoof....I have no experience with this on a shod hoof.
Though, my experience is in an area with lots of hard ground. I have no experience in the swamps or very wet ground.
Truth passes through three stages. First it is ridiculed. Second it is violently opposed. Third it is accepted as self evident.