Had I to give advice to writers (and I do not think they need it, because everyone has to find out things for himself), I would tell them simply this; I would ask them to tamper as little as they can with their own work. I do not think tinkering does any good. The moment comes when one has found out what one can do - when one has found one's natural voice, one's rhythm. Then I do not think that slight emendations should prove useful.
Jorge Luis Borges