Yeah, I could see it being an issue for some less-common type of indicator, but everyone who drives knows what a blinker looks like. Nobody would mistake it for anything other than the right hand turn signal.
Hell, I wouldn't even notice the shape of the light; all you need to notice while driving is the presence of a flashing light on the right side of the vehicle - if you're looking intently enough to notice the shape of the light, you're not paying enough attention to everything else on the road.