The information I've personally seen, of which part of it is posted above, states that vectoring of VDSL circuits will only be at the DSLAM. This is called NEXT (Near-end cross-talk).
If the 'noise' is then effectively wiped out at source through the application of pre-compensation factors, maybe the effects of FEXT (Far end) is minimal or negligible ?? I don't know, I'm not clued-up in the slightest with vectoring technology. I'm just re-posting part of what has come from our Chief Engineers office.