Now we have Ion "Watcher" Hazzikostas' explanation of the changes and why they were made, and it's a pretty interesting read if you're into encounter design and its implementation. Just some selected bits of information from the post:
- Originally on the PTR Heroic Norushen had a 'draw' mechanic that would have prevented the brute-force method, but it was removed because it had bad effects once gear improved, forcing groups to throttle their DPS.
- The intent isn't to increase encounter difficulty - the problem isn't that the fight is too easy, it's that people are just skipping the mechanics entirely.
- Going back to reference the Encounter Design Dev Watercooler, Watcher mentions that "a major factor when it comes to deciding whether to make changes to address an unintended strategy is whether the approach actually involves interesting gameplay." - I think it's fair to say that just throwing DPS at it so you can avoid the mechanics isn't all that interesting.
- The difference between the changes to Thok this week and Norushen in the upcoming reset are profoundly the difference between a bugfix (Thok was always intended to have Acceleration on all difficulties save Raid Finder, it was simply accidentally turned off on all other difficulties as well as Raid Finder) and a decision to change an encounter to close off an approach that was never intended. That's why Thok was hotfixed immediately, but Norushen is being changed with the server reset so it affects all guilds equally.