I'll generally give a real quick flip of the brights. Most of the time, if the oncoming driver is already dimmed, they'll flash brights just as info, which is fine. My husband is much nicer than I am......he never, ever flashes his brights into oncoming traffic. Ever.  Like I say, he's nicer than I am.

What has my knickers in a knot right now is the big-tires-jacked-up-go-get-'em-6"-cannon-exhaust-pipe pickups around here that have an added aftermarket LED light bar mounted at the center lower part of the grill of the truck...........right at eye level to oncoming traffic. The d***ed things do not/will not dim, and are the most blinding things I've ever seen. I keep thinking a Highway Patrol person will get an eyeful of them shortly and they'll be disconnected, but it apparently hasn't happened yet.