I think that would make for interesting CR for sure! Shepard has a tendency to let her emotions do the talking, but she'd be a lot more level-headed (and have razor sharp focus) when it comes to the mission.

Disagreements or not, all she'd care about is getting the job done and she'll do what she must to see it through. As long as no one gets in her way, CR won't just turn completely negative over an argument, if it even comes to that.