Blinkage

[NirvanaMan]

Turn indicators should be used to indicate intention whether changing lanes or making a proper turn.

One of the reasons we in America have so many accidents with such low speed limits is our inability to properly adhere to the rules of the road. Of course, our licensing requirements are rather lax, but still, in Europe using a signal and utilizing proper lanes (left for passing, right for slow) contributes their on the road safety.

In short, yes you should use signals. However, since many consider the signal as an indication to close the gap to prevent said lane change, combative measures are sometimes required.

Prepare the cannons.