Friends don't let friends strobe white.
And queue the never-ending argument...
I make a point of making sure my headlight isn't pointing horizontal or up, probably casting down about 20 feet in front of me. Even more of an angle on the winter bike, but I do find that us year round riders seem to have the headlights adjusted properly. I'm never getting blinded by fellow riders in the winter, but always have this issue on the shoulder seasons.