Fifth in an on-again, off-again, off-again series of posts on Capitol Hill publications.

On March 29, the National Journal announced that then-Politico Managing Editor Tim Grieve would be taking over as editor of NationalJournal.com, a brand name in Washington journalism that has struggled to find its footing in recent years. At the time, Politico Editor-in-Chief John Harris issued a snarky staff e-mail saying that Grieve’s new mission was “to help rejuvenate National Journal.” It also noted that Grieve would be leaving Politico forthwith, per mutual accord.

Yet Grieve doesn’t start as head of NationalJournal.com till May 10, according to spokesman Ben Fishel.

Did the hard-charging Grieve want to see the world and take up a new hobby before seizing the helm of NationalJournal.com? No, it’s far more boring than all that. Like many folks at Politico, Grieve was bound by contract, and according to National Journal’s Fishel, that contract expires “around May 9.”

To unpack this situation, Politico bosses determined that Grieve should bolt Politico upon finalization of his deal with NationalJournal.com. Yet Grieve couldn’t just head on over to NationalJournal.com and start work, because of his contractual obligations to Politico, which apparently wouldn’t release him a few weeks early. All of this leads to a scenario that you don’t often see in these straitened times: Politico appears to be paying Grieve to just hang out.

Possible explanations:

• Politico is a generous news outlet: Grieve has embodied Politico’s workaholic journalistic ethic ever since he joined the team, working on congressional coverage and launching Politico Pro, the site’s premium subscription service. Perhaps Harris & Co. just wanted to reward the guy.

•  Enough contract-busting at Politico! As Huffington Post’s Michael Calderone reported last June, Politico employment contracts are written in iron. Yet somehow former Politico reporter Ben Smith managed to skip out months before his deal expired. And in that time, he launched BuzzFeed, an outlet that usurped Politico’s former role as the news site that all media critics must write about. That can’t happen again!

•  Politico regards National Journal/NationalJournal.com as a serious competitor. Otherwise, why delay the accession of one of your folks to its helm?

Politico Executive Editor Jim VandeHei declined to comment on the record for this story.

Grieve declined to comment on the record for this story.

The Series So Far:

One: Troubles ahead for Capitol Hill publications?

Two: What’s the real leader among Capitol Hill publications?

Three: Roll Call’s six-year strategic response to Politico

Four: Politico aces PR

Erik Wemple writes the Erik Wemple blog, where he reports and opines on media organizations of all sorts.