Crazy? No. The timing and optics would be wrong since Sanders wouldn't help Harris' campaign play to its advantages. Finding younger candidates with consistent and (hopefully) progressive records, who aren't currently targets for the Right, and who hold little political baggage, is a better play.

By the same reasoning I think Newsom and Buttigieg aren't good picks even though they'd do well in the role. The new Dem Pres campaign should make sure the Right's propagandists have to work hard at effective attack ads. Running any Left-Wing Face misses this initiative.

For context: I'm still bitter about Bernie being pushed out of previous Presidential campaign runs, still think he was the best choice both times, and know he'd make a great VP.