It ought to be tough for Guess? (NYSE:GES) shareholders to remain calm, cool, and collected these days. Month after month, quarter after quarter, the resurgent retailer keeps putting up great sales growth, and the stock has risen to match.

December's results were no different -- stronger than usual, even. Comparable-store sales rose 17.5%, and total retail sales soared 27.4% from last year's period.

That's better than last month's good showing, although this time around, the firm didn't use the magic words "larger percentage of full-price sales," which accompanied the prior month's 15.8% same-store sales growth. That little phrase is music to my ears, because full-priced sales mean better margins for Guess?, and better profits for shareholders like me.

Of course, bigger sales on existing fixed costs mean better margins anyway, and for the quarter, Guess put up 15.9% same-store sales growth and 25.6% retail sales growth. That's likely to fuel another earnings "surprise" by the time the full results roll around, mostly because analysts have had a heck of a time getting a bead on just what Guess' earning power is.

Growing sales and growing profits are only the beginning here. My favorite part of the Guess? story is that it still seems no one is paying attention. Average daily dollar volume is only about $23 million. Few analysts follow the firm (about half the amount who spend their time scrutinizing its peers), and most of those who do are wide of the mark.

And in what I consider another vote of confidence for any stock, Guess's Yahoo! Finance shenanigans quotient is very low. As opposed to the hundreds of sniping messages you'll get from the keyboard heroes pumping and bashing peers like True Religion (NYSE:TRLG), American Eagle Outfitters (NASDAQ:AEOS), Aeropostale (NYSE:ARO), or Abercrombie and Fitch (NYSE:ANF), Guess? has one lonely, spelling-challenged basher.

Solid results, a rising stock, and still relatively unloved? That's the definition of stock-market opportunity, which is why I'm not planning to shed my shares. And it's why I suggest that my fellow Fools take a look at the details when the fourth quarter and full-year statements hit the wires.

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Seth Jayson doesn't bother trying to make specific guesses about retail earnings. Vaguely right is better than precisely wrong. At the time of publication, he had shares of Guess?, American Eagle, and Aeropostale. View his stock holdings and Fool profile here. Fool rules are here.