A good example of Blizzard choosing to go the other direction would be C’thun.
There was a giant wall in the fight, while some people claimed it was impossible, other theory crafters have stated with modern class stacking and enough time and gear farming it would have been theoretically possible.
Blizzard waited forever to apply any fixes to the fight, it was something like 80 days. By the time a fix was finally implemented, enough guilds had reached said wall that when it came down a ton of guilds got the kill within such a short period that the accomplishment was arguably diluted.
This is obviously the most extreme example of Blizzard choosing to implement fixes on bosses, but the point remains the same.
A “fast” fix benefits guilds in the lead, as they get to begin working on whatever new phase opens up due to said fix.
In this case I would agree with you that Method received the bigger advantage due to changes, I am only trying to highlight that waiting longer would not make it “fair”. Rather the advantage would be shifted to guilds 3-4-5-6-7-8-9 etc to reach the “wall”.
If Blizzard had waited to implement the fix 2 weeks from now, and some random guild that had reached the wall 5-6 days after Limit and Method snuck in and secured world first, it would feel like a hollow victory, or if they waited so long and nerfs were so heavy handed that 10 guilds killed it within a 24 hour period, it would also leave you feeling like there wasn’t a true victor.
In my opinion, quickly implemented “light” nerfs are the best solution.
I am not arguing that the way this race played out was 100% fair, just that waiting for reset is not necessarily better. I don’t know that there is a solution that is across the board fair, other than a global release where Blizzard does not offer any changes whatsoever until the boss dies, but this presents a whole new set of potential problems. (not the global release, I think that Blizzard should 100% do this next raid tier)