I've chased down (dont always catch up) and confronted. Generally with the adrenaline being pumping this becomes more about me being angry and loud than sucessfully educating anyone.
I tend to regret it afterwards, since all I end up remembering is the anger and no sense of accomplishment.
On the other hand, when I dont confront I tend to feel bullied and it eats away at me over time.
Feels bad either way.
I try to avoid riding in areas that have been problems, both to avoid the traffic and to stave off flashbacks.
Hmmmh, about the only time it went sorta OK (emotionally), was chasing down an suv with my u-lock held high for him to see. Ended up in a residential area, clearly he lived nearby, and he ended up not going home but instead circled back towards the freeway. I guess I really made him fear for retaliation right where it'd hurt - at home and not in the damn suv.
Probably didn't paint a good picture of cylists that day, but at least a driver realized that there was a real world outside the car.