I was looking around for T13 Spanish guide videos on youtube and found this one:
https://www.youtube.com/watch?v=AwS-rHtemVw

As you can see on the left there's clearly a precise timer for every single skill from the boss and a timer on the bottom left. I work in 3d and video editing and i honestly think this is not video edited and its part of some sort of 3th party program to know exactly when the skills of the bosses are done.

Plus i asked further a few guys i know from that server about the creators of this video. They said that their FC brag a lot about how easy they make the content. IMO if this is real its very bad because not only takes the fun out of the game but also makes it VERY easy for people who actually have not any skill whatsoever or intent to progress further. But i don´t know if this stuff is actually allowed/real. Thats why i post it here to discuss about it and see different comments and figure out my doubts about this.