"Ah, yeah, your dad told me about that." James had mixed feelings about 'Junior's' cavalier attitude about the hex. On the one hand, from what Harry had said it was pretty serious, and Harry would probably prefer his son take it more seriously. Given his relationship with Harry, James felt a bit obligated to try and be stern on the subject.
On the other hand, this was probably exactly how James would have behaved if it had been him.
"It's not necessarily a good club to be in," he remarked wryly, a compromise of sorts. "Besides, what happens once you play that card a few times and then they go and save your life? Then you're really in for it."
His namesake's bluntness surprised a laugh out of him. "Hey now. From what I hear, your dad got into more than his share of scrapes when he was younger." As if 'scrapes' could begin to describe them! "Maybe all Marauders need to retire eventually. Leave the field to the new kids." He winked at James Sirius.