I don't know if propecia works better or worse for diffuse thinners. I've heard arguments for either side. Being a diffuse thinner myself, I can tell you about my experience. I have been using propecia for two years. When I started I thought I was losing my hair fast (which is probably an exageration). Propecia has slowed the balding process considerably. The front has continued to thin (very slowly), but my crown has thickened a little bit. All in all, the drug has helped.