re: windshield washer fluid etiquette on the roadway

I've only ever done that to people who follow too closely. I hold it for a count of 15 to 20 depending how far up my arse their car is and they usually back off. Although, this one time I did it and the guy pulled around in front of me and let the washer fluid flow. I just laughed but apparently he was really butt hurt about it. Sorry for partying