Healing w Herbs

[Alex Koponen]

http://abroere.xs4all.nl/pnp/NMI_rarity.htm lists a number of herbs that
add specific amounts to the HC.
It states:
The healing herbs in a healing kit are usually cinquefoil.
Cinquefoil +10 HC *
Bandages +5 to HC for bandaged wounds. 1-6' needed per use.

  Now I have a trained healer with a healing kit and bandages. Some poor
guy comes to me all cut up and wants my help. So I use the healing skills
with the kit and bandages.

  Do I just get what it states on B1 p.27 for the healing skill?
I suspect so since the skill calls for access to a healing kit which
includes herbs and bandages.
  However, I note that Cinquefoil and Bandages together give a +15% bonus
to HC. The Healer skill gives 2xEL bonus to HC (plus a StB to the next
roll). One has to be an EL8 Healer before the 15% bonus from Cinquefoil and
Bandages is matched (actually exceeded). And what if one has one of the
other herbs?
  Do the herbs (and bandages) each give a specific bonus to HC? Regardless
of who applies it (Goddess of Healing or Bonehead without a Clue)? How many
herbs can be used at once?
  Should one calculate based on Healer or Herbalist EL, or roll, how
effective (what HC bonus) the herb will be? If so, what is an easy way to
calculate it?