I came round the corner behind a truck so couldnt see the van in time before I realised I was now on a single carraigeway
how close were you to the back of the truck? If you cant see his mirrors he cant see you.
Also, if you had merged from dual into single carriageway you surely noticed the lanes merging, hatching / road markings / end of dual carriageway signs? Not to mention the oncoming traffic in your lane?
If not, let me know the next time you're on the A9 and i'll avoid it.