If you paste material to each cubes one by one with Material Editor open and frontmost, then you can get above result (image on the right: I moved one of cubes to show its boundary). Texture positions are matched :-)
If you select all cubes and paste with Material Editor closed (or background), then your result would be something like this (for the text "test" texture, Negative Z is disabled. Centered by method B pasting, this texture gives no effect at all to the cubes). Exactly same results with Master Material.