I'm not saying that moving people are a complete showstopper for epidemiologists, what I'm saying is that it make the map visualization a poor fit for the task

I'm not saying that moving people are a complete showstopper for epidemiologists, what I'm saying is that it make the map visualization a poor fit for the task because it will induce the casual reader with access to only the map (that is, not epidemiologists with access to the full data) into making wrong conclusions.