Well I have housed an elegance coral well over two years before. I haven't heard any theory around the miracle mud, but If the mud gives off beneficial minerals, vitamines, etc....its going to be good for just about everything in my mind.
The key to my succcess was that I kept the elegance fed. It liked mysis and brine both. I feed it about once a week. Mine liked moderate water flow...not constant. I kept it in the mid area of the tank.... I always keep the calucium level high too due to a lps, sps tank along with the keeping up with the other reef supliments.
Good luck......
Oh I lost mine when I first tried the tropic marine calcium product. It said you could add it to the water column in your display tank, and I tried it. The calcuim didn't totally disapate and landed on the elegance and burnt it up. I have not purchased one since, but they are a great addition to the aquarium....
Hope this helps.