I use it mostly in my
compost pile to get the process going in the fall.
My compost pile is mostly maple and poplar leaves and there are a lot of them right after I rake.
I also use a broadcast spreader in the late winter, right after the snow melts to put some on the lawn. I've heard that chicken poo can burn lawn if too much is applied directly but I think it gets a good chance to soak in before the grass starts to grow in the spring this way.
I also drag the mostly composted leaves over the lawn once the grass starts growing then rake them back up. This is a nice way of separating the composted stuff from the un-composted stuff.
It's hard to give you a before and after.
Just before I bought my house, the previous owner replaced the cepttic system and put down a new lawn. He was a Scott's 4 step kind of guy so the lawn looked good when I bought the house, even though there was less than 2" of good soil. The lawn died shortly after I bought the house. It's taken me a few years to get it back without using chemical fertilizers.
Another factor is my daughter's rabbit.
We've always had one and I usually throw a few handfuls of his pellets on the lawn whenever I clean out the hutch. They don't seem to burn the lawn. I'm not sure what affect they have.