FORTUNE — Hewlett-Packard, the world’s biggest computer maker, announced that it’s planning to spin off its personal computer business and will buy the UK-based software developer Autonomy for about $10 billion. The news allowed HP stock to fight a disastrous tape for a nanosecond (up 8.3% at one point) but the shares soon joined the rest of the known world in free-fall. They closed the day down almost 6%.

It’s not a surprising move, even for a company that doubled down on PCs less than a decade ago via its 2002 merger with Compaq Computer. Most people — yours truly included — thought the deal was idiotic from the very day it was announced, evoking that old chestnut, “two drunks leaning on each other to stay upright.” But Carly Fiorina, then CEO of the storied technology company, rammed the deal down shareholders’ throats — shareholders that included a steaming mad Walter Hewlett, son of the company’s founder.

Fiorina got the boot from the company on February 9, 2005 for failing to deliver on the promise of the merger — news of her ouster sent the stock soaring 6.9%. It seems the way to make money on HP (HPQ) is to wait for it to do something stupid, give them five years or so to be able to gracefully reverse course, and buy in anticipation of the eventual announcement. (Let’s not even get into the whole scandal of Mark Hurd and the pretty PR woman that got him booted from HP. We’ve never really gotten to the bottom of that one, have we?)

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Sure, Fiorina left HP six years ago, but today’s news is the real end of her tenure. Yes, she was a failed California senatorial candidate in 2010, but did she ever really seriously think she’d win? On the other hand, she certainly spent a lot — $5.5 million of her own cash — on her folly. (Among the ladies of technology, Meg Whitman blew far more money in the gubernatorial race — $143.6 million — but she is much wealthier than Fiorina.)

Back to HP and the closing of the Fiorina era. Billions of dollars, tens of thousands of layoffs, and a computer paradigm shift later (from PC to tablet, courtesy of Apple’s (AAPL) Steve Jobs), and one of the dumbest decisions in corporate memory is finally being unwound. You’ve got to give it to her, though: she got the top job and she made a bold move, which at least made watching the company more fun than checking the ticker tape on Dell (DELL) or IBM (IBM). But that still doesn’t mean the deal wasn’t dumb.

Maybe someone should have told her that running for office on that kind of track record is destined to be a failed gambit, even if you are a hard-nosed Republican in a state needed a desperate dose of financial discipline. Maybe someone did, and she ignored them. And why not? Fiorina has a habit of getting credit for things beyond her control—her appointment to HP came after a stint in sales at Lucent, which, while praised, came during an era when any fool with a briefcase and a dictionary of telecommunications terms could have sold a few million bucks worth of gear every week.

Is Walter Hewlett — who fought tooth and nail with Fiorina — having the last laugh? Maybe not. The HP of today is back to coughing on IBM’s exhaust, after a brief pre-Carly moment when it looked like it might gain a step on Big Blue.

Thanks to Carly, that notion is off the table. You’ll see her elected Senator before that happens.