In condensed form: New player hits the lv80, and has been running the LFD for the last 10 levels. He has visited all the instances a couple of times at least, knows to handle them at least reasonably and starts gearing up with emblems from the heroics. There is no primer in-game to tell him what to concentrate on, how to improve and how to gear, really.
Gear gets up to raid levels, even though the 'low tier' raiding is going further away in every content patch. Naxx and Ulduar have been voided for either being 'too boring' or 'not of any value in gearing'. There is no in-game primer whatsoever to tell the the newcomer anything about the raiding part. No information about raids and raiding at all.
Being the casual slacker-moron, playing only now and then, this feller wants to experience the content. Funnily enough he wants to spend his time in the game rather than going through the off game material required to participate the group functions. Being as casual as he is, or as hardcore as he can, he is seriously deprived from the information which might make his playing more enjoyable.
So he takes his stand, plays whenever he likes and cares Jack about the raiding which is as mysterious to him as the finesses of the Algalon fight. It's just a myth.
Until he miraculously encounters another fellow, who has been playing for a long time and is willing to teach the poor time deprived gamer the ropes of the finer things in the game. The game gets new face and new lease in his life. And an extended subscription.
Can the game companies really rely on the off game information in making the game more accessible to the players with no -or limited- understanding of the game mechanics?