I’d not noticed this parallel before, but find it rather enlightening. I’ve always considered Arthur Weasley a complete and utter bastard for his treatment of Percy (possibly because I remember with shame an incident at school when I accidentally told the girl who won the art prize that she’d probably got it because the other two contenders, of whom I was one, had already won prizes in other subjects); it seems so trivializing and mean, however much there may be some small justification. I forgive it in Ron, who is young and thoroughly embarrassed by the whole situation (and Hermione could equally well have asked him to go to the ball with her), but it’s a serious black mark against Arthur. The group idea seems to make sense, especially with the group expanded to be the Order as well as the OBHWF.