I somehow suspect that ghostcrawler will be laughing inside everytime someone dies to this.

The difference being that the things you mentioned are not feats of strength. A feat of strength by blizzards definition is something that is perfectly acceptable to suddenly become impossible to get. The other things are standard achievements and as such there is the understanding that they will almost all be universally available for pretty much ever. Now what we have is something that wasn't outgeared but was in fact nerfed. To say it wasn't nerfed shows a lack of intellectual honesty and a certain degree of spin. Wether or not the nerf was a good thing or not is debateable, (I personally fall into the "slap in the face" crowd, although I wouldn't use such vulger termanology in describing it) but you cannot honestly deny that it was in fact a nerf of the achievement, and nerfing something that required such an amazing gut wrenching solo grind to obtain and showed true dedication to something so small as getting this Feat of Strength in which the only benefit is in the feat itself and the title, then nerfing the difficulty by about 30-40% of the time and gold spent on obtaining it letting others get it right after being told to hurry up or it's gonna go away by blizzard really is a poor move on Blizzards part, especially for those that did hurry up and grinded out the rep at the end when we were flat out told by Blizzard that it's going away.
Basically it shows a huge lack of integrity on Blizzards part. We questioned their honesty before, but after Blizzard pulled this on people multiple times regarding this one achievement, we can't help but wonder if maybe they will change their mind and go back to the other way, after all, Blizzard has given us zero reason to trust them so far, why should we start now.
This signiture is brought to you by the letters F and U, and the number 2.
"I know your $14.99 entitles you to play the game your way, but the rest of the raid's $359.76 says know your role."