Before the Hall of Echoes I sent the herb runner out for Fanny Blossom. He seemed to get hurt a little more than normal (or at least it annoyed me more than when I wasn't trying to build up a stack of potions), but nowhere near as much as what you saw.
I had level 3 Master Herbalist from a jewellery bonus, so was mostly sending him out for Fanny Blossom, but did have him get Earth Root for rejuvenation potions, as well (ginseng was also required, but I had plenty already).
