The compound in Comfrey that prevents you from 'bulk drying' is Mucilage - 290,000 ppm
Almost all plants produce this one but some at much higher levels like aloe vera, fenugreek, flax, kelp, marshwallow, okra, chia seeds (try sprouting this some time), etc.
This one gives seaweed that slimy feeling or even rehydrated kelp meal. Anyway that's why you can't stack comfrey leaves if you're trying to dry them for storage.
CC
Almost all plants produce this one but some at much higher levels like aloe vera, fenugreek, flax, kelp, marshwallow, okra, chia seeds (try sprouting this some time), etc.
This one gives seaweed that slimy feeling or even rehydrated kelp meal. Anyway that's why you can't stack comfrey leaves if you're trying to dry them for storage.
CC