Yep, I know I wasn't supposed to write any more columns this year, but this one couldn't wait.

You should've known there would've been trouble at Canadian software maker

Corel

(CORL)

the minute I took it out of my

Garbage Index. (Note to my assistant

Mark Martinez

:

Put it back in!

) I took it out, with reluctance, because it had turned a few quarters of profits. I thought it belonged with the rest of those pseudo-Linux plays because it is a company with a not-so-brilliant past, but it had been a theme stock. And theme stocks don't belong in the Garbage Index.

The lessons are twofold: The first, in retrospect, occurred in an interview CEO Michael Cowpland had last week on

CNBC

with David Faber and Bob Sellers. Faber asked him something about the company's strategy, and Cowpland responded that the recent performance of the company's stock (from around 5 to 45 in the span of about two months) validates the company's strategy. (It's now trading at around 13.) The lesson here is that in irrational markets like these, the performance of stocks validate

nothing

other than they have a mind of their own.

I learned that lesson years ago when I was writing about

Media Vision

, which was Silicon Valley's highest flyer of the day and now is kaput. I had written the latest in a series of questioning columns and the stock, in classic

Greenberg Effect style, zoomed. The CEO, who has been indicted on charges of securities fraud and faces trial in several months, called me and boasted something like, "You see, your short-selling friends are wrong." Wrong about the stock, maybe, but not the fundamentals, which eventually catch up with all companies.

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The second lesson, as I've mentioned here and in a recent issue of

Fortune

, is that this year companies will experience the audit from hell. Auditors are under more pressure than ever not to miss any questionable accounting issues, and the audit comes to a head in the fourth quarter. Corel didn't say anything about the auditors in its press release, but whenever a company suddenly warns that it will miss its fourth quarter -- especially a week after the CEO was on national TV touting his company's stock, you can't help but wonder whether there wasn't an audit-related issue. That's especially true when, as part of its warning, the company mentions, as Corel did, that the problem was identified after "a detailed analysis of channel sell-through."

As for the Garbage Index: It's down about 2% since its creation.

Now, back to my vacation. And I hope you enjoy your holidays.

Herb Greenberg writes daily for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, though he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. He welcomes your feedback at

herb@thestreet.com. Greenberg also writes a monthly column for Fortune.

Mark Martinez assisted with the reporting of this column.