New TfL's HGV's can't see you for s*** poster

Another way to see it is that a lack of any road markings means the drver has to concentrate harder and will drive more slowly and cautiously.

This is plausible, I've seen drivers end up being careful when the traffic light brokes, ironically more careful than the temporary light that was set up.

However I doubt the lack of road markings would encourage them to concentrate harder, we do need road marking to know when's a junction approaching/where to turn.