The main reason for the German conclusion is that a blinking light is harder to keep track of and I agree with that. The best is a wide, multi-led, bar that is always on but most people don't want a 5 inch bar on the back of their bike for aesthetic reasons.
A blinking light can certainly draw attention but if you want to use those, combine an attention-drawing flash with a steady light.
But perhaps you like the idea of the
Lightskin seatpost light?