I had an experience with comfrey healing things a little "too quickly". But am very happy I used it anyway. Just would do it differently next time. I had a complete laceration of two tendons on the back of my hand. I used comfrey poultices daily during the post-operative recovery. The skin healed so quickly that the stitches started healing into the skin before they could dissolve. Instead of pulling them out as this was happening, I snipped them shorter. I should have pulled them out. The laceration & repair healed so quickly that I was left with a whole row of bumps from stitches under the skin. Eventually they dissolved. But if I ever use comfrey like this again, I'll pull the stitches early!!