The New Kind of Flesh: "Like men in teams, who jump"

The comparison modifies "armies" or "flow," or both, from the previous line.  An army is like a team, and certainly some concerted actions of armies are more like "flow," seen from the vantage of strategic action, than the simpler Newtonian vectors and forces.  There is the possibility of a chaotic or Brownian interaction among particles (the individual "jumpers," as for example D-Day paratroopers), and the effect of flow is pressure.  The comma breaks the line metrically, and also creates another ambiguity, the referent of "who" -- could "who" be the teams, jumping collectively, or would it necessarily be the "men" as I had at first assumed on this reading?