The general point is that defense major shapeshifter should be the best at the defensive thing they do. Certainly vs. any stock build (not accounting for high level gear).
Dillo fits in this regard, to me... I don't think anything can get that high with DR. Maybe a Lich, but that's basically a quest class. Porc is similar. Not the best DR, but DR + reflective damage.
The damage avoidance forms feel like they aren't that. They aren't as good as the arial or w-elf build outlined, and obviously that build kicks a mongoose's ass in basically every other way. Even if we remove cabal (no spell evasion/spellbane) I'm betting the warrior comes out ahead still.