Hi Vaughan,
We have used Commissioners Quay(cut) on a number of occasions for visits into Norwich, as you say over the bridge and up the lane to the bus stop, the bus stop is on the left after you get to top of the lane.
We also tend to use the cut for mooring practice on our training days if nobody is moored there, it is a good place to see dragon flies. There was reports of people cutting or letting lines go last season, so if stopping overnight pick the port side of the cut and put down your mud weight, even though the risk of drifting is minimal.
Regards
Alan