Reddit reviews The Discovery of the 'Titanic

Agreed, but as i said before, i believe not finding it makes it more, not less, likely that it's in the sea (somewhere). Finding an aircraft debris field or a whole aircraft is considerably easier to do on land where satellites, people, and other aircraft could see it.
In the ocean you can miss debris by a few metres and have no idea it's there. I highly recommend reading Dr Ballard's account of the search for Titanic for an idea what this is like; and that was a big ship sitting upright (in 2) on a flat and firm bottom (ooh err). AF447, as others have pointed out, they knew where it went down and it still took a rethink and new search area to find.

Oh, that was one I just found from a quick google. Argo took tons of photos of the wreckage when Dr. Ballard found the debris field, and there were many photos similar to that. I think there's a bunch in this book