I normally come through Walworth/E&C twice a day, and you're right, matching speed is important. Carrying my camping kit, I wasn't so confident of doing that. There are a lot of drivers round there who haven't a clue about lanes, and that's why one young woman got killed there not so long ago.
The cycle route goes either side of the RABs, through a series of 'facilities', starting, if you're heading north, with a sharp left turn into a narrow lane.