We had a bit of a conversation over this. I think I said how difficult it was to find the wreck even with the equipment we now have. Here's a sonar sweep of the SS Terra Nova (Scott's ship of the 1914 expedition) taken 2 years ago. It's in one piece, in 1000' of water on a smooth sea floor, but still took 70 years to find even though they knew where it went down off Greenland.
As I write this drift debris is being examined in Australia, that MIGHT JUST belong to MH370. The relatives deserve to know what happened.