Help on growing out a horse's tail?

My mare had a tail that was decent in length but it thinned out towards the end, So i chopped off the part of her tail that was thinned out because i'd rather have a horse with a short tail for a little while rather than have a tail that became really thin towards the bottom. I would like to know if chopping a little of her tail would help her tail grow a bit longer....and how often i should groom her tail...i use a conditioner before i brush it so i don't really pull any strands of hair out except a few.....And would braiding it every time i ride(couple times a week) cause more breakage, i braid loosely.