Interesting. Perhaps its different when your ahead of the curve and actually make some of those ''BiS builds''. There is very rarely a true best build. Even more so if the abilities are not the same one with a different color.
I think its more a problem of some people wanting something to believe in. A ''skill build'' to believe in, haha.
Bit a little more serious, really people should get over themselves.
It's particular silly to require of people to ''spec like this because I read this in a PRO guide''.
If you've ever been part of any high level build/spec discussion then you would know there much of such builds are up for debate.
The only times there are clear distinctions is when something is clearly for an entirely different area of the game (IE PvP: raid bosses/mobs are usually immune to CC), or when one of the abilities is imbalanced compared to the others.