Keep in mind that an extra variable here is whether or not your character detects a shift in the veil as a shift in the veil. Generally, being Battle or Nexus is better than being a random guy with detect magic, being higher level is better than lower, and I want to say discern spell helps too.

So if you give an item to a courier/Tahren and it's of middling value, maybe the hero Battle scout registers that as a shift and your midlevel uncaballed transmuter doesn't.