<<At the moment - amazingly - there is no defined path on the approach across London with residents not knowing exactly the noise they will get.>>
Amazingly! Where do they get these people?
Looks like that quote has now been removed from the article in question.
Having said that, there does appear to be a fairly common misconception among the general public that arrival routes are defined in the same way as departure ones.
While BAA have a good series of factsheets on their website explaining how things work, they are quite hard to find. By contrast, their page on "Arrival procedures" talks about CDAs and joining points, but makes no reference at all to the routes taken between the hold and the ILS.
Heathrow Noise: Arrival procedures