I grow a lot of nettles for food and insect habitat. I'm also curious about what they bring to the microbial diet of the invisible herd that makes up the soil web. When my nettles get long and leggy, I usually just chop and drop them or toss them into the
compost heap. My assumption is that anything beneficial they offer to the greater biosphere is going to be slowly released as the leaves break down. I'm too busy to make compost/comfrey/nettle tea and then find the time to spray it. But my assumption is that anything good in the tea would also be present (albeit more slowly released) in old fashioned chop-and-drop mulching, yes?
"The rule of no realm is mine. But all worthy things that are in peril as the world now stands, these are my care. And for my part, I shall not wholly fail in my task if anything that passes through this night can still grow fairer or bear fruit and flower again in days to come. For I too am a steward. Did you not know?" Gandolf