Angus Bryant wrote:

Seems that one (albeit costly) way to improve the NLL capacity and
congestion issue would be to build a dive-under to swap the NLL/ELL
passenger service and freight trains somewhere between Dalston and the
Canonbury curve. This would allow ELL trains from the south to
access the Canonbury curve and the NLL diverging later at Camden
without crossing the frieght lines.

Is that practical, surely the CTRL runs below that section of the NLL?
Perhaps raising the approach to Dalston (from Bishopsgate), flying over and
dropping down onto the north side of the NLL would be a cheaper solution?