Take a break: avoiding congestion in ant colonies and elsewhere

A recent paper in Science is introduced by the NY Times under this headline:

The Secret to Ant Efficiency Is Idleness

Here's the paper:
Collective clog control: Optimizing traffic flow in confined biological and robophysical excavation
J. Aguilar, D. Monaenkova, V. Linevich, W. Savoie, B. Dutta, H.-S. Kuan,  M. D. Betterton, M. A. D. Goodisman, D. I. Goldman

Here's the abstract of the paper (preceded by another description, perhaps written by a writer for Science(?) meant to be more intelligible...

When fewer workers are more efficient:
"A narrow passageway can easily become clogged or jammed if too much traffic tries to enter at once or there is competition between the flow of traffic in each direction. Aguilar et al. studied the collective excavation observed when ants build their nests. Because of the unequal workload distribution, the optimal excavation rate is achieved when a part of the ant collective is inactive. Numerical simulations and the behavior of robotic ants mimic the behavior of the colony."

Abstract: Groups of interacting active particles, insects, or humans can form clusters that hinder the goals of the collective; therefore, development of robust strategies for control of such clogs is essential, particularly in confined environments. Our biological and robophysical excavation experiments, supported by computational and theoretical models, reveal that digging performance can be robustly optimized within the constraints of narrow tunnels by individual idleness and retreating. Tools from the study of dense particulate ensembles elucidate how idleness reduces the frequency of flow-stopping clogs and how selective retreating reduces cluster dissolution time for the rare clusters that still occur. Our results point to strategies by which dense active matter and swarms can become task capable without sophisticated sensing, planning, and global control of the collective.