A few major comments can be found below concerning R2 the possible presence of type IV pili in their EM images, some confusion regarding descriptions of motility analysis and others.
The authors state that supracellular structures emerge from unordered motion and are therefore not encoded for genetically. While their model for spiral formation does not require a genetic program for controlling motility, it may not always be the case for other supercellular structures. In other words, it may not always be true that supercellular structures are not genetically determined.