This morning on my way to work I stopped because an articulated lorry had got stuck. It had turned into a road which was too small for it and was in the process of reversing out.
As it was just beginning to rain, I got off and sheltered under a tree to put some waterproofs on.
The trailer was blocking about 75% of the road that it was reversing into, hazard lights and reversing lights were on and it was moving back slowly. Motor vehicles in both directions were stopped.
Over the next minute or so 4 cyclists came along and all of them cut round the back of the (moving) trailer. Of the four of them, three were commuters on decent bikes (one with tri-bars), all wearing helmets and hi-viz. One was a sandwich delivery guy with a trailer.
The risk to them maybe wasn't huge, but it was present and they couldn't judge whether the lorry was going to increase it's reversing speed.