How does a Washington rumor get started? That’s the question I asked when reading the overwrought speculation about Evan Bayh, the former senator from Indiana, taking Sherrod Brown’s position as the top Democrat on the Senate Banking Committee.

Bayh has a very good chance to win back his Senate seat, and he served on the Banking Committee from 2000 to 2010. That actually gives him more seniority than Brown. Should Democrats take back the Senate in the fall, and should Bayh’s seniority be recognized by the majority leader, he would be in line to snatch the chairmanship of the committee.

That’s the theory of a bunch of K Street lobbyists, anyway, and it sounds like what they would ask for if they rubbed a genie lamp. After all, Bayh sits on the board of Fifth Third Bank and is a partner at McGuire Woods, the corporate law firm that counts a number of global banks as clients. He’s even worked at private equity firm Apollo Global Management, one of those “shadow banks” Hillary Clinton has warned are the real threat to the financial system. Compared to a populist reformer like Brown, who authored the legislation that would have broken up the largest U.S. banks, I’m sure the industry would welcome a Bayh leapfrog. So they’ve talked themselves into believing that somebody promised Bayh the Banking Committee chair if he entered the race for Senate.

The only problem with the idea is that it’s preposterous. While there is no formal rule about whether a senator gets back their seniority if they win a non-consecutive term, the history of the Senate firmly establishes that they don’t. Frank Lautenberg didn’t get his seniority back in 2003; neither did Dan Coats in 2011. Heck, Hubert Humphrey returned to the Senate in 1971, after a stint as vice president under Lyndon Johnson, and even he didn’t get his seniority back.

There’s a good reason for that. While the decision on seniority would be up to Chuck Schumer, the presumptive Democratic Senate leader, he probably doesn’t want to piss off the majority of his colleagues right off the bat. Bayh’s restored seniority would elevate him beyond 30 current senators, all of whom have an interest in rejecting such a move, since seniority matters for committee assignments and chairmanships.