Dynamic Visual Obstruction is the term for when a moving vehicle (or propped vehicle) blocks another vehicle’s sightlines. This phenomenon often occurs at signalised intersections when a right turn bay blocks the view for a turning driver/rider (and approaching driver/rider). 

In many jurisdictions, the default for signalised intersections is to allow filtering and if there is a crash history then implement turn controls. We think this is the wrong way around – the default should be fully controlled right turns, and where risk is proven to be low a filtering may be permitted.