Seriously all you need to worry about is the color of the light. Check local vehicular code for allowable colors. Whoever said in the video "never attach anything to the helmet" is acting like an idiot or thinks he's talking to idiots.

If this works for you, maybe you can combine it with elbow band turn signals (I've been tempted myself). I'd activate it with a mercury switch, swing the elbow up the blinker turns on.