[Shadowstep]

I recently stumbled upon a post regarding essence optimization.  It was stated that via some rule, your total essence lost to Cyber/BioWare = 1 x The Greater + 0.5 the Smaller of the two. So if you lost 4 Essence to Cyber and 3.9 to Bio...you'd be at 5.95 Essence Lost (4*1+3.9*1/2).

I can't seem to find any rule that confirms this. Maybe I don't know where to look. So could someone please confirm is such a rule exists and where it is from.

Note: It's entirely possible I stumbled on a SR3 thread and got confused.

[Teknodragon]

SR4A, page 86, under Cyberware and Bioware:

Essence losses from cyberware and bioware are tracked separately.
Only the higher of the two totals deducts from Essence in full, with
the other deducting at half. For example, if a character has an Essence
loss of 1.5 from cyberware and 2.5 from bioware, then the character’s
Essence is 6 – 2.5 (full bioware) – 0.75 (half cyberware), or 2.75.
Players should keep track of both, as it’s possible one can outpace the
other as the character implants more cyber or bio into his body.