Well, if commentators had looked at the track record of returning C.E.O.s — boomerang C.E.O.s, as they’re sometimes called — that’s precisely what they’d have predicted. A 2014 study found that profitability at companies run by boomerang C.E.O.s fell slightly, and an earlier study detected no significant difference in long-term performance between firms that reappointed a former C.E.O. and ones that hired someone new.

But the more common boomerang CEO is a founder or board member who has held onto much of his equity stake and is still quite involved with the firm. One prominent example: Howard Schultz, the Starbucks founder who had been CEO from 1987 to 2000 and then, after the company lost its footing, returned in 2008. Schultz still runs the company, which has thrived under his leadership.

Companies change a lot in a few years. Is there a temptation for boomerang CEOs to turn back the clock and do things the old way?