If a player chooses to gem in ways which are generally not advocated and can achieve the same results or better, then who is to say they are incorrect? As Lore has reiterated numerous times throughout his videos, the value a player brings to the table is not based on their gear, it is the ability to play their class. This has been true since the start of WoW and it's predecessors.
I'm not talking about someone having a differing idea about what a certain class should be gemming for.
Where is the value of a hunter gemming stamina, mp5 or spirit because he had a blue socket, and thought he had to put a blue gem in there because the socket was blue? Without the color coding, he might have gone ahead and put something more useful in.
Or, if he really has no clue what he's doing with gems, he'll still put in something funky. But at least he wasn't misled by the system itself.
You and I, and everyone else here knows you don't have to obey socket colors, and knows that there are times when you can and should go for a socket bonus. Or you may get some notion that breaks with conventional wisdom, but I'll bet that it isn't based on the fact that you had a blue socket (or whatever) on your gear.
But I can't even hazard a guess at how many people I've had to tell that you don't need to obey socket colors. Each time I mention it, they are suprised at the news, thankful that I told them, and promptly do something more sensible with their gems.
What this means to me, is that a significant portion of the player base finds the current system unintuitive and misleading. It tricks them into making poor choices.