I tried fermented feed back in the winter and they liked it a lot and as you say the waste was minimal. Trouble I had was it was too cold in my shop to keep the feed warm enough to ferment. Are you all using some type of heated vessel or are you fermenting the feed in your house? I read that egg production is better with less waste and consumption and the benefits go on and on. If I can figure out where to set up my ferment I will go that route.
Do you back fill the ferment to keep it continuous or are you doing separate containers throughout the week? And do you use the pellets or crumble? Reason I ask is I fermented some pellets and they did good but I thought maybe the crumbles may be better for some reason but can't think why except maybe for stiring in the existing if back filling daily.
I live in southern AZ so cold is rarely a problem here. Quite the opposite, actually, which is why I indicated wet/fermented. I have three 5-gallon buckets that I mix the feed in, mixing one bucket of feed per night. Each bucket usually rests for 2-3 days maximum depending on the birds' appetites. The summers are harder because if I do more than soak the feed for one day it will quickly begin to go moldy, so summer is wet feed only. And the feed I use is typically mash, not pellets or crumble, but I have used those as well. The only backfill comes from any feed left in the bucket when I begin to mix more. I sometimes add whey from yogurt we eat, hot pepper flakes, kefir, ACV, powdered probiotics, etc depending on what I have available and what I think my flock may need.