Another downside is that while it does prevent spoilers, RCV doesn’t prevent other forms of vote splitting. It keeps an unlikely outlier candidate from tanking the consensus candidate, but it doesn't prevent splits between three or more viable candidates. This is especially problematic because one most important supposed qualities of RCV, according to its advocates, is that it makes more candidates more viable.

It also gets rid of people who are too dumb to understand RCV. Hee hee. Intellectual filter on the voting population. :)