Nightblade "Master Assassin" passive bug

IInsomniac

When doing some penetration related testing on my nightblade character I noticed that the assassination skill line passive "master assassin" was not working as described. Instead of giving me extra penetration when flanking, it always gave me the penetration - unless my character was facing south. I tested this outside of my house as well and got the same results. Instead of giving pen depending on my character's orientation to the enemy it seems to be giving penetration depending on my character's orientation to the compass.

Here is a video I made on the bug - all the testing in it is done in my house but as mentioned before I have tried this on overland mobs with the the same results.
https://youtu.be/y6rrhbfrxiE

IInsomniac

After some feedback I did some more testing and this bug seems to be purely visual, as the damage calculation does seem to works as intended.
I did some more tests attacking dummies from different angles with one surprise attack each, wearing the same gear and making sure the hit is a crit for comparison.
A friend joined me to test as well so we can have some more results to compare.
When facing south the flanked target consistently took more damage than the target facing us.
So this is definitely still a bug but it seems to be of pure visual nature, not just in addons but also in the base game stat UI.
This definitely threw me off as I stumbled across it while testing but I am relieved to see that it works as intended for the actual damage calculation. So there should be no problems with this in actual content.

I will make updates in the video title and description to reflect this.