Crusader Codex Ignore Def.

Not as far as I know.

We didn't do scientific measurements, but my we did a series of Hob King PQ's to get the set, and my hermit friend noticed a definite difference in damage on Rex before and after he completed the set, which was his first and gives 15% ignore def.

Once the maintenance concludes, and assuming it really fixes the set switching, we can test more methodically.

There's no need to.
It's quite obvious all it does is fetch potential lines, so it's the same thing.