It will sharpen chains but usualy needs some work. Several articles on it over on the chainsaw forum one of which was written by me
Mine sees very limited use, basicaly chains that are rocked or hit objects imbedded in the wood. I have watched many people try to hand file and the biggest obsticle I see is they try to do it with the saw rocking around, cant be done. Stump vise is mandatory (IMO) in the field and in the shop you mount the saw by the bar in a vise. It takes an expert to file a chain while sitting on the tailgate of a pick up, when it is held still chain filing becomes easy. Online guides at all the chain Mfg sites show the basics better than I can explain them. The Oregon file plates sold anywhere the chains are sold are a good "crutch" for learning and those that cant see or dont care to learn to do it right as are the various other gizmos sold by Husky, Carton and others. Otherwise just a file and a decent file handle is used. Filing IMO is just plain all around better than grinding. The only thing a grinder has on filing is speed, everything else is a minus.