Chewy — Today at 12:48 PM
Well, mechanically is almost a carbon copy to uwow (thus far)
balance wise, now this is a different conversation.
Tank damage seems to be abit all over the place, but it did not really become apparent until we reached dragons. And generally speaking dragons deal alot of extra damage on most skills.

Dragons also still retain the good old 2y meme fogs making it extra hard.

And theres a new bug in the fight (or old one that we never faced) where you could have a flower spawn in the wall which will reset the fight instantly. Obviously  this can be avoided by players never going near the walls, but adding the fogs together with the basic stun mechanic of the fight, and the lack of space... well you sometimes see yourself forced to be near a wall, which leads to the potential of a flower spawning in it. 
But yeah the damage intake is considerably higher than intended when all is said and done. Some mechanics range upwards to 20-30% more.
Chewy — Today at 1:21 PM
I wish we woulve had more time to test damage on the ptr, because of all the variable.
But even compared to uwow u can already see that the damage is similar or higher (despite uwow having 25-10% buff on fights in our logs, to 0 here)
Image
uwowx5 bood dk with similar gear/stats at dragons
the last number is average damage taken
and thats in here
Image
at the time of that uwow kill the boss had 10% dmg dealt increase, and even then is nowhere close to the damage taken in mythicwow
Thats just one example of many
Also the fact that the fight above was 5mins long (a kill), and the fight below, our best attempt was 3 and half minutes, and already took more damage.
Chewy — Today at 1:35 PM
Ill not sugarcoat it.

Right now, we will need to put alot of work towards finding ways to cheese specific mechanics in order to survive them. (cheese not in the exploit way, but use known spells/mechanics to completely avoid them if possible, like spellwarding and bubbles on elethre to single soak winds and sacrifice a single player)

Which leads to the group needing to invest into other character classes to adapt.
Our healing comp is literaly worthless against the tank damage we are facing right now. Let alone raid damage, but thats more manageable.
Chewy — Today at 1:44 PM
I could go out of my way, and actually meticulously parse every single ounce of data, but if history is to be taken to heart.

1 i doubt any fixes would occur in a timely manner.
2 its a thing that i do not wish to do right now, i woulve been willing to if you had approached me to help with testing earlier, but now in between dealing with the progression and real life, my free available time is cut down severely.
3 even if the numbers are trully tweaked/fixed down to more reasonable levels (not even retail, just reasonable), that doesnt guarantee anything dying if i dont invest the time to coordinate the group, which goes back to point 2.

I wont lie that i slacked once i heard midranger say things were fine, i didnt bother to check specific damage, because i asumed he woulve executed more than 2 braincells for it. But here we are now.

even then, even if i woulve gone out of my way to do that 2 days ago, it wouldnt had been fixed today (heck, ursoc is still bugged so, and its a simple delay of a spell to fix the issue, the only reason we killed it was because we could brute force it by dps and hps alone).

When you asked me if 1m unmitigated vs plate armor AA was good damage (on cenarius) i meant it when i said yes. But after looking at the AA tank damage, im concerned that you might have meant general damage done of all normals, and not just cenarius.

Because even nythendra was doing absurdly high tank damage. Which shouldnt had been the case.
Infact, looking at dragons damage, WITH mitigations, dragons damage is right now higher than cenarius ever was with auto attacks.
https://www.warcraftlogs.com/reports/4hdTp6LQP7KRDX2t 

here are our logs from yesterday incase you wish to skim through
(sidenote, for some reason mythic logs are scuffier than hc, which is weird, im not sure why but logging mythic is consideraly buggier than hc and nm, so things like ilvl/stats/replay function and such are not really working properly)