Additives that please?

Well, I can't prove with statistics because the experts that I would trust for the information, like Bornmann, Toonen or Shimek for example, have said that there IS no proof that any of those additions benefit corals and have stated that additional iodine is not needed by the shrimp for molts as there is sufficient in the water anyway.
In one of the online mags there is a chart showing that the levels of iodine and others in our salt water is many many times higher than normal ocean water. Boomer is constantly referring people to this chart as most people are just not aware that in order to produce salts with needed levels in some things, trace elements get added in proportions not equal to ocean water.
IMO, if you want to feed the corals, one of the best things you can do is to add phyto occasionally, but preferably add gut loaded rotifers.
There are "snow" products out there that could benefit your corals but as the products are almost all water you are spending a lot for virtually nothing. I think it was Shimek that did or had done an analysis on coral/tank foods. There may be some newer foods on the market, but if you can't see anything in them, or if the contents are larger than rotifers, then it probably won't help much.
As for proving what one says, maybe you should be asking Jake Adams for proof of what he said. I have never seen any proof in my years on the net.
I'm sure many more knowledgeable authors than Jake would also be interested in seeing it.
That being said, I've been told that if you look hard enough you can find "proof" for anything, on the internet.