Yes, it is a pity. 230 tons of structure cannot sink into the ocean without signs: papers, wood, plastics, baggages, clothes... many of these should have been found ! This is not the shooting of another LOST episode. I think they simply have NO CLUE where could be the plane. But after a week, those many debrises will be already at Dakar or Miami, or at Antarctica... I think they will not find the recorders not because of the depth, but because of the bad location. If they want to really find it at all :s