I had the same happen on the FROGs ride last week - the elevated crossing with the stripy painting seems to be the prompt. Give way signs on the cycle path but nothing for the motorist.Used to see the same happening at the humps in Hay Street, Subi - not any more.
Plenty of people still wonder across Rokeby Rd on those humps thinking they have right of way, not sure if the cars stop for people. I do if it looks like a "little old lady".
Fortunately most cars on Rokeby are going pretty slow.
Unfortunately when you are stuck behind one on your bike.