I was at Hackney Downs Station yesterday when a Stansted Express train
crawled through at little more than walking pace. The alignment of this route
through inner East London precludes fast running. Why, I wondered, don't they
route the train via Stratford?

The route between Liverpool Street and Stratford allows rapid movement and
once Stratford is passed, the route between Stratford and Tottenham Hale is
also far better aligned than the line via Hackney.

Presumably there must be a good reason for continuing with the tortuous
Hackney route but does anyone know what it is? Shortage of capacity between
Liverpool Street and Stratford? Too much time lost negotiating the Stratford
curve? Any ideas?