Basil Jet wrote on 06 Feb 2018 at 22:54 ...

https://en.m.wikipedia.org/wiki/Haringey_Heartlands

Mary Neuner Road opened in approx October 2009, but since then nothing
much appears to have happened in the area. There are no properties
accessed from the new road, and although it's a handy bypass when there
is a traffic jam on Hornsey Park Road, I suspect the business case for
the road would not stack up on that basis alone. The road only really
makes sense as an access route for the derelict land either side, but it
seems odd that the road opened nine years or more before it was needed.

The business case was apparently that it would relieve congestion. See this BBC news report from November 2008:
http://www.bbc.co.uk/london/content/..._feature.shtml
(The 2014 date at the top is probably when it was archived.)
--
Richard J.
(to email me, swap 'uk' and 'yon' in address)