The reason was that I was being imprecise with my number.

The 8-bit value 188 converted to unit range is 188 / 255 = 0.737254902

I was only using the first four digits before. Now I can't see the difference even with M=10000

In fact, even at M = 1 BILLION you can't see the difference.

---

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)