User blog comment:CandyAnaisWatterson777/WHY?/@comment-27607014-20180701233313/@comment-11883116-20180702014434

I wish TD fans would stop overusing the term "character derailment". What happened to Courtney in SMS wasn't character derailment. In fact, she was more in character than in majority of the season, especially the last few episodes that focused on her overly sweet and out of character friendship with Gwen.

Dave wasn't derailed either. He was just developed more (granted, in unsympathetic way, but character development can be unsympathetic as well). Sometimes flanderized too.