Yes, it can make sense for some applications (when used with care). But check the article, they're not using fluid dynamics, they actually try to estimate capa

Yes, it can make sense for some applications (when used with care). But check the article, they're not using fluid dynamics, they actually try to estimate capacity/load using period averages and basic arithmetic. Such an approach can lead to a massive underestimation of required capacity even in contexts where arrivals aren't as batched as they are in train stations (like a call center).