This is only party true. If one had about 450SP he would be forced to vote with full strength on the first posts and less on the others. There is no way how to turn that around and I think that the option simply can’t hurt anyone. It seems only natural to me that after 4x stronger vote is established, a slider should be available 4x faster. I mean, where is the harm?
Also you’re taking in account your knowledge, but most of the new users hear "10 votes per day" and that’s the knowledge they act with. It takes time before they realize this fact and the only harmed subject is then the traffic on minnow’s posts. And again, what harm would the slider do?