I think internal feeding is an insurance for those hives that start to brood, and get a late cold snap or a period of bad weather, and guards against brood starving and the bees ripping everything back out.
I have never seen the huge increases some suggest in my cold climate based on internal feeding while it's still cold outside and the bees are not flying. Without nectar and pollen being brought in from field bees, bees are very reluctant to raise brood beyond a small amount.
Same as I see in the fall. After bees come through the summer dearth, you can feed to add weight. But you want to stimulate brood, make them go out of the hive and get it.
While bees will start brooding in my area with the first maples and other early blossoms, this time period is also seen with days if not weeks of cold weather to follow. So I feed sometimes to maintain the brood production and keep them starving or cannibalizing the young.
But I don't think bees are inclined to raise massive amounts of brood in cold weather for the mere fact you throw in a patty or put on a feeder. That's just food for the bees. Not really a trigger mechanism to all of sudden have bees think they should be raising brood.....when they are not even flying.
I'm sure feeding in areas where it's bit warmer, and perhaps even with little actual nectar being produced, that bees will brood more based on some feed. but the warmth, the bees activities, and other factors all contribute also.