One stock that I think has traded irrationally is Deckers Outdoor Corp. (NASDAQ: DECK).

Shares of the UGG and Teva footwear company had fallen to $80 per share in late October, but lost nearly 50% of its value from there in November.

Considering that the company increased guidance on Oct. 23, this move made little sense.

When I last wrote about DECK in July, shares were trading for more than $100, but well off their highs above $160. At that time, I suggested that investors resist the urge to buy the beaten-down stock, no matter how tempting.

It wasn't that I didn't believe in the potential of the company. Instead, the macro picture being as it was at that time suggested waiting for a better entry point. I thought below $80 would make sense.

I was right about waiting, although I did not think the stock would sink to less than $50 as it did in late November. Obviously something was amiss given that DECK's performance was quite stellar.

I've seen too many high-flying fashion stocks crater back to earth to take bullishness with companies like Deckers Outdoor (NASDAQ: DECK), the maker of Uggs, too seriously. Remember L.A. Gear?

But Deckers has had an amazing run this year, hitting a new 52-week high on Friday, making it a solid triple for the year.

According to Fortune, "Now, analysts are predicting even more upside for Deckers' stock. The reason? While other brands have been heavily discounted this holiday season, Ugg boots, which can cost upward of $200 a pair, are selling at full-price in most major department and specialty stores. More full-price sales mean fatter profits for the all-important fourth quarter."

It's all very exciting but I think investors need to be very careful. Uggs account for nearly 90% of Deckers' revenue, far outshining their Simple and Teva brands.

A bet on Deckers is a bet on the continued success of a pretty bizarre fashion trend -- at 50 times earnings and more than 5 times sales.

It's easy to be bullish when everything is going well, but traders will be dumping this one like they dumped Crocs (NASDAQ: CROX) at the first sign of slowing growth. And at some point, won't people have all the Uggs they need?

With about 19% of the float short, it looks like more than a few investors are lining up to bet signs of weakness are near.