The Delirious mod's threat reduction does not increase with rank

The new Delirious mod doesn't seem to be scaling properly, if its description is accurate. At all ranks, it reads "3.6% of your Toxic typed attack damage pre-damage mitigation reduces your outgoing Threat."

The Crushing damage equivalent, Unknown Force, starts at 9.6% threat reduction at rank 3, increasing to 13% at rank 4.

For both Delirious and Unknown Force, the secondary effect of increasing your primary superstat when dealing the associated damage type looks to be scaling properly, starting at 9.3 with rank 3 and increasing to 10 at rank 4.