hmm interesting, Scatty inplies she doesn't belive in it but I think she belives the Witch, maybe that's why she didn't categorize her w/ the others.
the quote also says they can see through
time, nnot the singular threads themselves. Seems to me what they do are predictions w/o considering process they go through. while the Witch is more of an observer not interfering w/ of each thread so as not to affect the outcome. Just like what she did in the Alchemyst. She knew there was one thread in w/c Hekate will die, she did not warn the Goddess because she didn't want to interfere w/ the flow of time.