Eric Mangini has strong ties to San Francisco 49ers management and coaches dating back at least 15 years.
The thought of the 49ers consulting with him has obvious appeal given those connections and given Mangini's background as a defensive coordinator in particular.
Mangini, now an NFL analyst for ESPN, is reportedly among multiple football people the 49ers have considered adding as a consultant. I don't know the extent of communications between Mangini and the team, but the subject raises a few thoughts in general:
Open to ideas: The 49ers are coming off a Super Bowl appearance. They have succeeded beyond reasonable expectations under coach Jim Harbaugh and general manager Trent Baalke. But they still appear open to outside ideas. That is good. The 49ers have over the years welcomed into their organization people with a range of professional backgrounds, some from outside the league. Paraag Marathe, Gideon Yu and Mark Wan come to mind as prominent examples.
Potential pitfalls: Bringing on a high-profile former defensive coordinator in any capacity would raise questions about the current defensive coordinator. Vic Fangio has, by all accounts, done a fantastic job for the 49ers. Mangini, if hired, might help with the offense. That's great, but he's still a high-profile defensive coach and his presence in any coaching capacity would invite questions about where the initial job might lead.
Ties to 49ers: Mangini worked with Baalke when both were with the New York Jets. He has also worked with 49ers special-teams coach Brad Seely. If Harbaugh were to consider adding Mangini, I would see that as evidence of his complete trust in Seely.
Personnel feel: Finding creative ways to use personnel could be a strength for Mangini. The 49ers have already been quite creative on that front, particularly on offense. Mangini's familiarity with Baalke from their Jets days, coupled with his coaching experience, could add value as the 49ers seek ways to maximize their personnel.
That is probably enough on the subject until we know whether this marks the beginning of the story or the end of it.