Here we have an example of an insignificant review that made a insignificant alteration to an insignificant statistic. What is significant, and troubling, is that this was dealt with by some means other than simply ignoring it. The need was seen to take it down, for the sanctity of that dubious top 10 list.
The list itself of course invites corruption, as people seek to stack the vote in one way or another to get their course a cut above others they possibly if not likely have not played. And the cure seems to be worse than the disease - if we get rid of that 1 star from a guy who was having a bad day, how many 5 stars do we get rid of because of home course bias? How many 3.5s or 4s were just put in to sabotage a rival's stats? This then becomes less about user reviews, and turns more into a game of lobbying the moderator for some intervention in the interest of getting a "justice" that is ultimately impossible to achieve.