The BBC reporter probably has a child at the school. :)
Seriously though - it is an excellent school - good leadership and aspirational for all its children (FSM and Special Needs) - this is what makes it different from other schools in 'affluent' areas. But it does get a huge boost from the aspirational parents who move to the area just to get access to the school. So a bit chicken/egg really.
The Head has done amazing things - and is now part of consortium to try and help other schools (especially those on the other side of Haringey) learn from what they have achieved - this is where they can really start to make a difference for other disadvantaged kids - so the ripple effect goes far beyond these PISA scores.