The Moorgate - Liverpool Street link is actually potentially useful for me, as i live on a line which runs into Moorgate and occasionally travel to the frontier

The Moorgate - Liverpool Street link is actually potentially useful for me, as i live on a line which runs into Moorgate and occasionally travel to the frontiers of civilisation from Liverpool Street, so now i can change trains without having to catch the tube or leave and re-enter the stations. Although whether the deep route is actually any quicker than the route through the streets is yet to be determined.