As one of the "mob" referred to by T-B-G above, I would have to agree that Geoff does go for a lighter shade colour palette and have heard him say on occasion that road surfaces are often portrayed as being rather too dark.
Black Lion's roads are a lighter grey, and would suggest that the double page spread picture on pages 84/5 of issue 270 is a more accurate reflection of the layout when viewed in the flesh. If you look carefully behind the railings above the platform, the road pictured there does, in my view, show the colour of the roads more accurately.
Looking out of my window, there is an area of tarmac, a drive admittedly, which is around 15 years old which has weathered to a very light colour indeed, and I think Geoff did explain his thoughts on colours very well in the article itself.
Whatever your views, it is my opinion that Black Lion Crossing is a stunning creation, by one of the most talented all round modellers currently active.