Her "menial tantrums" caused him to cross the double yellow and then bang into the curb. Wouldn't turning on the charm require a minute or two to get his anger under control? I guess that can all be explained away by just saying he's not normal.
Saying that Gabby is the automatic victim doesn't mean we should put our brains on autopilot.
I don't think her "tantrums' menial or otherwise were responsible for Brian driving at, I think, 45mph in a 15mph zone and not stopping for the police for quite some time.
Possibly, her 'menial tantrums' were because they were speeding away from the police and she didn't want to experience a forced police stop or the risk of being shot.