Mikio Takebayashi and Masamistu Onishi's paper starts from a very topical and stimulating pointnamely, the (lack of) robustness of airline networks to investigate whether high-speed rail (HSR) services could help in more resilient networks in case of sudden adverse events. The authors present a model for addressing such situations. Beyond the apparent sophistication of mathematical formulations and the fact that the authors have certainly done their best, several of their assumptions are questionable.