Not just irrelevant, but that guide was also responsible for either creating or at least maintaining the legitimacy of certain bad habits by players who'd rather trust a company that prints the guide once, and never again, or the players dedicated enough to do the math, or experienced enough to know effective methods. I'm of the opinion that you should always trust user written/maintained guides and advice rather than advice written once by a third party company. This is doubly true for MMO's, where the environment changes rapidly, and anything not able to be updated constantly will become incomplete within months, and obsolete soon after.
I'm sure there will be a hard copy of some "all inclusive" guide, because there's money to be made off of people who will trust it. I'm also sure that more effective guides will be released by people who only care about their place in the community, or have a desire to help others.
Things WoW did not invent: