Everyone in here seems to be making the assumption that people will see the arrow and honor it as an arrow instead of subconsciously just seeing tail light and

Everyone in here seems to be making the assumption that people will see the arrow and honor it as an arrow instead of subconsciously just seeing tail light and acting accordingly. Driving is so second nature to the overwhelming majority of drivers that they won't even see the arrow. If this arrow was orange and 4ft tall like the arrows used to control traffic flow you might have a case.