You ran the 450 and the 550 backwards in the equation. 450->550 is a 22.2% threat increase not 18%.
I remember a time when threat management is a legit skill required of dps players.Now they just want tanks to have infinite threat.
I think we need a brand new "Onyxia Wipe Animation" about how NOT to pull threat off your tanks. Since Legion, where Blizz buffed tank threat by like 1000x as mentioned above, DPS got used to going all out on pulls and even tho Blizz reduced that threat multiplier quiet a bit in BfA, it was still not a huge issue since Blizz buffed threat again during BfA when needed.As they say, old habits die hard! most of the DPS still wanna unload on pulls and one of the biggest reason for that is of course they are staring at their damage meters while smashing keyboard to see numbers go up and up, fast and faster. This issue is mostly in random pugs since your regular friends/guildies that you team up with for pushing keys know how to play well together. Those regular groups mostly also happen to have a MD class in the group and threat on pulls become a non issue.I've seen myself while tanking on two different classes in random pugs, even a well geared high io score Hunter or Rogue simply don't bother using MD on tanks. Not to mention a certain melee classes (guess who) go all out on pull tunnling the same melee mob (and not bothering with caster mobs interrupts) and then complain about getting smashed by that melee mob.Again, threat issue is mostly in random pugs only where sometimes a higher geared/skilled/io DPS who wanna do their weekly vault fillers AS FAST AS THEY CAN, regardless of how is rest of the group specially tank or healer. Increasing threat multiplier is a band-aid fix, which is good but, the main issue is player's behavior and how they play.Some of the DPS really need that new Onyxia Wipe Animation 😉
update: the threat buff didn't really do much they need 50% more or something I'm still eating thru threat