The article you linked to goes on and on about the exact issue I mentioned. IRV tends to select for extremist candidates. Condorcet methods tend to punish them. The article tries to defend this, but I see this as a very bad outcome. Extremist candidates can do much more harm than good. Centrist candidates are more rational and tend to be less likely to do crazy things. Condorcet methods ensure the winner will be the best possible compromise, IRV gives very inconsistent behavior but can favor extremists, but can also punish third parties (IRV still suffers from vote splitting in many cases, see video I posted.)