How does threaten work?

i think my merc isn't high enough to go there (nor has the codex) so i have to wait for your results. godspeed

So my friend was dealing the dmg this time, seeing how mercedes defense break is buggy and always shows 808. Insight physical resist doesnt seem to be like that.

His PDR lines as Xenon using blade dancing:

Weapon 30% potential line 5% passive
6% pirate deck
5% top
10% Hat
20%+20%/40% spikes royale

Screenshot of his stats:

 Spoiler

40% one should push it to 96.2% 20%+20% should be 108%.

Im happy with the results seeing how this benefits me but I was wrong. It is a flat 40% on spikes royale.

Before spikes royale

 Spoiler

After:

 Spoiler

Im 99% sure that paladin threaten works exactly the same, glad I was wrong, less cubing for PDR