Yeah it's a 2d geometry, of course some of the cables will cross. The other reason that overlapping would be an issue is if they need to pull up a section to r

Yeah it's a 2d geometry, of course some of the cables will cross. The other reason that overlapping would be an issue is if they need to pull up a section to repair it and it's directly under another cable. But the ocean is really damn big and there are only O(100s) of submarine cables. In both the burying in shallow water case, and the deep water maintenance case, I'm guessing the chances of two cables being in the same place is very very small.