I have used the leaves in oil infusion. Plus, I keep tea tree oil on hand and it does help with some skin "stuff" but, I do know the oils help with the softening if that type of issue is present. Since I also make goat soap, most all of those oils are here at the house

Of course, being an adult male DS isn't one to "use as recommended"

You would think if it helped he would...BUT
I'm slowly cultivating more comfrey to use for the animals as part of their feed. They obviously love it because I have to fence it off to keep the starts growing! Good thing this is a plant that loves to grow!!! I would like to have about a 1/2 acre of it. High protein and huge vit/min accumulators. (just ordered more root stock last night) Chickens and goats fight for it. Plus great for fertilizer & compost activator. I want to get some wormwood, in near future...just for a couple large pots/tubs. I hear it's invasive.
Some plants I use little and it's easier to buy small amounts dried. Elderberries are my push this year -- wild here & I've found a large supply, so pick, freeze, juice when more time for that & syrup. I'm obsessed with this now.

It's odd as I haven't had a cold or flu in 20+ yrs but...others have so I have subjects to give it to. Well, salves last a long time & help when you need them. Most weeks we end up with a scratch or ten to be handled, so I try to have something on standby.