I think it had something to do with the fact that they were "masters of the basics" It somehow translates into Jimmies. Due to my lack of understanding Japanese, I really can't say much.

Also, I admit to not remembering who "that geezer" was, and I thought for the longest they were referring to Rokkaku's coach, and then I was like "O WAIT, IT'S YAMABUKI AND BANJI THE PEDOCREEPER :O"