Such a tactic might work, but I don’t know about the reasoning. They might seriously not know that they’re doing anything other than kidding around. It’s a bit much to assume they don’t have a better nature. Sometimes people just adopt a behaviour that they learned in one environment at some time or another and never grew out of it or invested enough thought to realise how it might affect people around them. Maybe that’s too much sympathy for someone being shitty but I just don’t know if I’d start with the assumption they have no better nature when there really might be a decent person behind it all that’s simply never been shown what they’re doing in a different light.
If it comes from someone they trust and wouldn’t want to offend they might take being honestly told about it seriously. Ironically though, I still think your approach could be a way to do things even if I don’t agree the person is beyond redemption and just deserves it. I’d just hope it shocks them out of it and prompts them to reflect.