The AMR simulator does not appear to properly handle the additional kill shots that are available from the Flayed Shot covenant ability. I looked over the implementation of this spell in the simulator wiki and my best guess as to the cause for this was that it is not accounting for the fact that the cooldown of Kill Shot is reset whenever Flayer’s Mark is cast. I could not find anything that appear to account for this spell interaction.
This is causing the AMR simulator to use Kill Shot approximately 1/4 as often as it should. I believe this also is affecting gearing strategies because the gear optimizer tends to favor other conduits over Empowered Release. I also suspect that it has a noticeable impact on the covenant rankings in the guide section of the site as well.
For reference:
AMR simulation results, 4 minute fight - 4.8 Kill Shots used:
https://www.askmrrobot.com/wow/simulator/report/1091a02d22a448e7845d73253c36868a
SIMC simulation results, 4 minute fight - 21 Kill Shots used:
https://www.raidbots.com/simbot/report/t6MZ3agUiA5AF3X3H1eqAA
Heroic Hungering Destroyer log, 3.75 minute fight - 18 Kill Shots used:
https://www.warcraftlogs.com/reports/jxZptzmyHh9L7qaf#fight=9&type=damage-done&source=2&cutoff=0