Hmm - after studying the math I used, I see another approach. The amplification factor used to trigger evaluation of the lace is in the PM:Enable Lace node - which label says you should set=1.

Well, if you set it to .1, then the entire lace map range [0 to 1] will be re-mapped to a tenth of that [0 to .1] - and this part of the map range is used only for opacity!!

---

Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)