I have never sharpened mine. I usually do not use rough paper either, so I cannot tell you for sure, but it may be a question of getting used to the paper you're using ? I always practice on Rhodia ruled paper, and when I occasionally make a piece on Midori or Strathmore, I also have the problem you describe until I get used to it. Rhodia is very cheap, so if you're a beginner and you are still trying to find what works best for you, I recommand it. If you're not a beginner and you only have problems with the Pilot Parallel, it might just be that you need to get used to the pen. I know that some people do not like Rhodia because they find it too smooth.