Winter is a slowdown time. Not just for chickens, either, and its a time to refresh and rebuild.
Egg laying is seasonal, for the most part, much as we want to think otherwise. This should be recognized in our zeal to keep 'em churning out the eggs.
Now you can "trick" chickens with artificial lighting to some degree, but it isnt like they go, "Oh hey theres more light now - it must be spring already, so I better start crankin 'em out for my beloved master..."
What you do as I understand it, is to just extend their season somewhat. They still slow down by some degree. Whats the predictable amount? I have no clue. Maybe they DONT and just burn out sooner. I have never fussed with all that lighting stuff, so cannot qualify as a chicken light expert.
The whole artificial light thing was conceived back when electric light became common place. It was seen as a way to help keep eggs going in the time of year when prices were the highest. Along with that was the idea of having to flocks: A spring/summer group and a winter laying flock.
With the advent of refrigeration and centralized factory methods, it fell from favor.