The Huffington Post has a way of squandering its own victories over the establishment press, and it's happened again: Larry Roberts, the investigations editor triumphantly lured from the Washington Post, has resigned.

Roberts was assigned to the Huffington Post Investigative Fund rather than the website proper, but, technicalities aside, his hiring last spring represented the crown atop a body of journalistically regal HuffPo hires, including fellow WaPo alumni Dan Froomkin and Antonio Vargas, plus the well-regarded founding editor of CNET News.com, Jai Singh.

We heard over the weekend Roberts had resigned the prior Thursday, and today Roberts clued in the full staff in a memo he helpfully forwarded to us:

Roberts' pride in his underlings aside, we've heard the investigative fund he worked for has yet to reach a comfortable working relationship with overseer Arianna Huffington or with the Huffington Post. As our own John Cook detailed in January, the charitable fund is supposed to be independent of HuffPo, but is heavily dependent on the website to run its stories, and even takes marching orders on some pieces from Arianna, who edits HuffPo and, simultaneously at the fund, assigns stories and sits on the board.

The fund also shares office space with the HuffPo's DC bureau, but word emanating from the bureau is that the fund seemed adrift, even abandoned in the absence of the sort of heavy-handed micromanaging Huffington exerted at HuffPo proper. Apparently the philanthropic entity had the worst of both worlds: There was no complete journalistic independence, since Arianna couldn't resist meddling in story selection; but there also wasn't the heavy front-page play and promotion that would have come from being truly integrated into HuffPo, since that sort of integration was forbidden. This explains the stories we've heard about HuffPo Fund freelancers getting confusing and contradictory messages about what sorts of articles the fund was interested in.

There's no denying Roberts scored some nice hits at the fund, including a series on mortgage fraud in Southern California that's been discussed as Pulitzer bait. But his departure will go down as another lost opportunity for HuffPo to elevate its image, just like the publication's "Off The Bus" experiment in citizen journalism, which scored two of the biggest reporting coups of the 2008 presidential election campaign season, only to see Arianna neglect the innovative project before handing it over to her godson. Like the investigative fund, Off The Bus received outside sponsorship. The fund took money from the Atlantic Philanthropies, Off The Bus was partly supported by New York University's NewAssignment.Net. As such, both projects presented Arianna a rare chance to build her brand with free support from outsiders.

Last May we wondered how long Roberts would last under Arianna, who can be "hell to work for," as we've documented in the past. Now we know: Less than a year. Given the state of the journalism job market, we can only hope her other hires are having a happier time of things.

UPDATE: We asked Roberts how he liked working with Arianna. He wrote back, "My note says it all, thanks." Funny, his note (above) doesn't say anything about the publisher. Then again, if you can't say something nice...