Body language alone triggers a twitch in the flag finger, but I think it really depends on what's being said. If case number one is a "All day long .... ALL DAY LONG" ... then it's appropriate to step in and tell white to get back to the huddle and watch the mouth. If it's a "Eat that, bitch," I gotta flag.
Maybe the R/U had a chat with their respective backfields and issued a warning? "Guys, players are getting too mouthy. That stops, now. Any more of that will not be tolerated." (Though that implied philosophy of altering standards is up for debate on its merits...)
Again, I'd have to know what was said.
I had a player look me right in the eye Saturday, and yell. "Oh, my GOD... Can't anybody block?" Mighta looked like he was yelling at me. He wasn't.
I had a player in the same game walk away from a tackle, look left casually and utter, "Suck my dick" to an opponent. Probably didn't look like much - but

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