While clearing some overhanging brush along the rail trail, I probably wedged a branch between the LC40 flashlight and the fairing:
Aaaand twisted it enough to fracture the mount:
A closer look shows the infill just ripped apart:
I can’t be sure that’s what happened, because the mount actually failed several miles later, after I hit one of the potholes along Raymond Avenue. Fortunately, I saw it swinging away from the fairing, hanging by its last few threads, and managed to grab it before it vanished.
I set Slic3r for 30% infill on the replacement, but the running light been riding my fairing for three years and seems strong enough under normal use.
The Smell of Molten Projects in the Morning 
Wouldn’t it be stronger to epoxy it back together?
Epoxy cures nearly every ill around here, but I admit to not even thinking of it for this particular malady.
Making the flashlight mount stronger just means something else will take more strain from whatever happens and, frankly, I’d rather replace the flashlight (or its mount) than, say, the fairing. Mary’s mount broke when the bike fell over on it, my inept brush-clearing may have killed this one, and both of ’em lasted years longer than I expected: they’re probably strong enough.
So far, so good, anyhow …