I do not do anything to my horse's hooves except pick them out. My horses have good, hardy feet so I really have never had an issue. I honestly wouldn't feel comfortable with doing any filing on my horses because I am not knowledgeable and don't know what I am doing. I'm afraid I would ruin something.
Lucky for me, my farrier tells me if I ever need anything to give him a call and he'll swing by and take a look. If we have a chip or something, he'll take care of it.