Showsheen! It's literally my all time go to for detangling tail, shine, and even shine in my boots! After every bath I spray it down my horses neck and butt (not saddle area for obvious reasons) and they dry so fricken shiny and soft. Also I use it straight before I go to the show ring to add some extra shine if needed. And if I don't have any boot shine in hand it works just as well to shine them up!
I couldn't live without showsheen! I use it every day to detangle my horses' tails and it works wonders on tails. The most important thing, though is never, ever brush the tail. This pulls out the hairs and leaves a stringy look to the tail. If you douse it in showsheen and go through the whole tail, esssentially picking individual hair by individual hair, this will make your horse's tail amazing. But, be careful not to do this too soon before putting boots on your horse, maybe for instance right before you ride, as it could make the hind boots slip around a little, as some of the show sheen has probably gotten on their hind legs. I also spray it on a horse's coat before I clip them, after giving them a bath. This allows the clippers to glide through the hair very easily and also helps with lines. I also dip my blades in show sheen to clean them out while I'm clipping. I buy most all of my show sheen on SmartPak! Hope this is useful!