I watched a special recently in which there were two black holes observed and there was a single star between them. Instead of doing what a single black hole would do- pull the star into/onto it with it's imense gravity- the star stayed relatively the way it was because the black holes were simply canceling out eachother. Well If they could do this with a star then they would be likely to be the same for a person. If a spaceship (far in the future obviously...) was to go between the two black holes it would likely survive too. Also, if they cancel eachother out visibly (with the star) then isn't it likely that they cancel eachother out not visibly? As in they would NOT affect space time except in their immediate area (itself)? Unlike other black holes which would effect everywhere.