This is a picture I saw recently where the UK Police illustrate the blind spots of trucks.
REF: http://www.crossrail.co.uk/construction/road-safety-information/lorry-driver-training
Cycle training literature says "There is no doubt that biking in the door zone is unsafe and even deadly."
REF: http://washcycle.typepad.com/home/2005/11/bike_lanes_in_t.html
Lucky Road designers clearly mark these no go areas of the road with
bright paint and cycle logos so show cyclists not to ride there. However as you
can see from this picture some cyclists are confused by these no go
warning signs.
REF: http://www.fahrradwien.at/blog/2013/09/06/mehr_sicherheit_durch_bikeboxen_in_wien/
So despite the good intentions to warn cyclists not to ride in these no go danger zones the markings cycle planners are using are confusing and one could easily conclude they are trying to kill cyclists.