On 2015\08\08 00:49, Charles Ellson wrote:

North of the Thames,
trains leave Highbury and Islington (also Canonbury) for Clapham
Junction in opposite directions; some are at identical departure times
(so you can choose the wrong platform rather than the wrong station).

I was going to say it doesn't matter much, because journey times are
similar, but the Shoreditch route cuts through zone 1 and the Willesden
route stays in zone 2. They could fix the problem by usually terminating
the via Peckham trains at Dalston Junction... they appear to run ever
single one to or from Highbury, giving Croydon and New Cross the Dalston
terminators.