My appy/draft gelding rubbed some tail off last year before he came to me. (most his mane, too) I used MTG over the winter - I'd apply it to the tail bone, leave it over night while he was stalled, and rinse it out in the morning. Kept his tail braided pretty much all winter, taking the braid out to brush every other day and re-braid. It was slower going than when you can just leave mtg on, but still grew in faster than just time alone. He has a nice full tail that reaches about 3/4 down past his hocks now.