Have you ever wondered how “Dick” became short for “Rick”?

Probably not. But it turns out that the reason, if the following video is accurate, is interesting.

I have two questions for the historical linguists in the room. First, is there a name for this rhymification effect? Is is common? Is it confined to certain regions or cultures? Is it linked to Cockney in some way?

OK, that was a lot of questions, but really, all the same question. My second one is simpler: Where does the phrase “Swinging dick” come in? It is a Britishism for, I think, Square Mile money managers and investors. According to something I saw on TV once.