(FAO @profk)
Here’s Mr pn’s route to work:
https://www.strava.com/activities/705726754
So from Peckham, go up the Surrey Canal path and then into Burgess Park. When you exit BP it’s mainly cycle superhighway, avoiding E&C. It’s twisty and turny but once you’ve memorised it, it’s fine. He says once you get onto Blackfriars Bridge there’s a cycle superhighway all the way to Clerkenwell and you should be able to turn off left somewhere to go to where you need to go.
I’d also look at Cycle Streets and see what their routes say. They normally give three options, going from quiet and slow, to busy and fast.