yes because possibility at 865 gear for 4 hours of hard work, with the other 4 hours giving 850 gear is totally worth it to a heroic/mythic raider... i did a full clear, 4 hours, not a single peice i could use out of that place dropped, there is only 1 item that is useful for me from that place and its the belt off maiden, and its only a +5 ilvl boost
i do agree with what your saying though, but most heroic or mythic raiders wont find use in karazhan