QUOTE (Cthulhudreams @ Mar 17 2008, 07:38 PM)
Yeah, it's a retcon in augementation that is kinda stupid. Making it universal seems both easier to understand and less abuseable.
And if you want to understand why it is stupid
It's not a retcon, unless I'm horrifically mistaken (page ref?) SR4, before Augmentation, is silent as to essence holes/healing. Additionally, there isn't any real trickery you can do with essence holes, if it looks like there is, you screwed up the math.
CEA: Cyber Essence Account = sum(current cyber essence costs) + remaining cyber essence hole
BEA: Bio Essence Account = sum(current cyber essence costs) + remaining bio essence hole
Current Essence = 6 - max(CEA, BEA) - min(CEA,BEA)/2 - Essence Drain/Loss from other sources
Additionally, you may want to look at
QUOTE (Augmentation pg 88)
Cellular Repair: ... even heals Essence loss inflicted by a critter with the Energy Drain or Essence Drain powers...
Revitalization
Revitalization is a recent breakthrough that repairs Essence
loss derived from invasive implantation. ... In game terms, revitalization regenerates the Essence “hole�
left by the removal of an implant from the body. ...
Which, AFAIK, are the definitive references to healing Essence loss. Note that Cellular Repair works on non implant essence loss and Revitalization works directly on essence holes from the removal of implants.
Also, in support of the formulas I list above, all references to essence holes are in terms of the amount of essence the implant (that was removed) cost, not in terms of the delta it actually caused to your essence when you installed it.