i will just say that mulch is great, but it can enrich the soil a lot to feed it sugars, molasses, whatever cheap carbs you can find, this is part of what the mulch is doing but it penetrates deeper sooner and it stimulates increase of population of bacteria and fungi inside the soil...

the mulch helps make it more hospitable for these tiny critters, and they are the life of the soil, far more important to the health of plants growing in it than mainstream chemical agriculture would let you know