I am not going to keep going around in circles, but I will end this by saying that if Chip Kelly "butted heads" with a known good guy, Jason Avant, then it doesn't make me feel all warmhearted about the guy. Simple as that.
"When it came to certain things, we butted heads sometimes-- route running and route technique," Avant explained. "So I knew I didn't fit his system."
They butted-heads over route running and route technique. Big deal. Two grown adults can have a disagreement about something without either one of them being an asshole. From reading Avant's quotes it sure doesn't sound like he is holding any type of grudge or special hatred for Kelly.