By applying a high-current pulse to a lithium-metal anode, the researchers were able to produce heat that wasn't enough to melt the lithium metal but was enough to encourage "extensive surface migration" of the lithium atoms. That essentially "healed" the lithium-metal anode of newly growing dendrites, which smoothed out the surface of the lithium anode again.
Not exactly the same phenomenon, but something similar, might be happening in LEAF batteries. I'd be the first to admit it's a long shot.
The research paper is behind a paywall. Ars Technica talks about the current density of a pulse but not its duration nor the temperature reached. There have been a lot of posts about battery degradation on MNL, but none that I know of discuss what chemical or mechanical changes cause it. In particular, I have no idea if there are dendrites in degraded LEAF batteries or even whether they have lithium metal anodes.
In a quirk of fate, one of the paper's authors has surname "Li".