Just read through the thread and I can't believe there are "die hard fans" who don't know who Terry Hanratty is. I wouldn't know him if I saw him in a bar today, but I sure as hell know the name and era the guy played.
I'm in no way, shape, or form a New York Yankees fan but they might be the only similar sports institution to compare Notre Dame football to. If the guy had said, "Joe Montana? Did he play for ND?" That's unforgivable and would require immediate surrender of both man and fan cards. It would be like saying, "I think I recognize the name Babe Ruth, but to be honest I'm not sure if he every played for the Yankees but I'm a die hard fan."
Terry Hanratty doesn't quite rise to that level, but it would be similar to a "die hard" Yankees fan not knowing who Thurmon Munson was. All Star, MVP, World Champion.
I do my best not to judge the "level of fandom" for good people who share a love of mine, but I'd roll my eyes at that one after the conversation ended if it happened in person.