People do complain about focus a lot. Rather than looking to their self to solve the problems, they blame it on new mechanics. Focus isn't the issue, the players are. WoW players have become so self-righteous and think they deserve everything handed to them on a silver platter. Blizzard knows this, and it's about time that they acknowledge their players are a bunch of whiny bitches.
Here's a solution. Get used to focus or re-roll a class that better fits your playstyle.
IT'S AMAZING how bad people are when they don't have spreadsheets and other resources to hold their hands and tell them how to play. I absolutely love watching people kick and scream because they have no will to actually learn themselves.
Here's a solution. Stop blaming the game and blame your lack of skill & lack of will to learn. You might have a fucking epiphany and beams of sunlight will shine down upon your face as God guides you to not being a damn turd.