Do you ride that commute in the dark? Didn't see much lighting especially through the wooded parts. Scary narrow cycle lane when the lorry passed you, yuk. At least your area seems to have cycle lanes that actually go somewhere and appear to be linked up. He probably let you pass so that you'd ride harder giving him the opportunity to choose when to speed past....Good point to let you go past just at the bottom on a climb just to see how you manage it....