When comparing AMR sims and SimC sims, the average damage of Kill Shot seems to be around 30% higher in AMR sims. Other physical abilities, such as auto attacks are nearly identical and the SimC reports show 29.99% mitigation on physical attacks.
My best effort calculation of base stats in addition to averaging buffs, procs, CDs, etc. weighted by uptime gives me a number similar to the AMR number before factoring in armor and a number similar to the SimC number after factoring in armor.
It may just be a coincidence that the mitigation from armor is approximately enough to account for this discrepancy, but there is a discrepancy and it’s enough to be noticeable.