Yes, you can communicate alot with drivers even though your face is hidden behind a helmet, and its better to use your hands with good gestures than bad as giving the people rude finger gestures only gets everyone worked up, then distracted mentally from the task of riding your bike.
I listened to a pod cast about a 'street whisperer' a guy who goes around and talks on street psychology to example... town councils etc and how to deal with car gatherings etc.
A interesting topic was the aggressive driver and your reaction to this behaviour was to wave confidently and look directly at them, one is they slow down to try and see if its someone they know ....you don't get the fight or flight reaction.
The other thing is hell that person knows me and how embarassing that ive been caught showing a side of me which i try to hide.
Another example is to get to know your neighbour a few doors down your street, wave at the guy down the street who speeds, when people know each other they tend to behave a little more responsibly as the now know the parents who live down the road with two kids that like to play around the street etc.
I just thought it was a interesting approach im not sure if i should try the waving vigourosly of the bike though!
Just remember... "wherever you go, there you are" .....Buckaroo Banzai 1984
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