For me, if I am losing a game against someone 10 pts lower then me, but also winning against someone else also 10 pts lower then me I would probably want to resign the lost game right before I win the other one in order to minimize my overall rating loss. There is nothing wrong with this, it is legal and within the rules. It is a type of strategy that I guess could be employed by someone trying to maximize their rating for getting into a tourney or something like that.