question about stealth detection range

So I was theory-crafting a set with as minimal stealth detection range as possible(5 night mother, 3 night terror, and 4 Darlock Brae for a total of -6 meters of detection). However, when I kill someone with the blade of woe, it always says I'm detected. So instead of 2 meter detection range, is it still a 8 meter detection range when I do that specifically?