Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of real-estate developer St. Joe (NYSE: JOE) jumped as high as 13.4% on above-average trading volume.

So what: A weekend article in Barron's showed that Glenrock Asset Management founder Michael Katz is long on St. Joe, and also highlights just how successful Katz's investment strategy has been. Katz picks his longs and shorts based on the quality of cash flows, much like we like to do here at the Fool.

Now what: Glenrock doesn't love all real estate plays equally, and has shorted New York-centered SL Green Realty (NYSE: SLG) among others. But St. Joe met Katz's stringent criteria: "We go for what we think are deeply undervalued stocks with lots of upside that we can buy at liquidation values or less." I just have to wonder whether he shouldn't have gone for a meatier REIT such as timberland specialist Rayonier (NYSE: RYN) instead, with its beefy dividend and four-star CAPS rating. St. Joe has had an active dividend policy since 2007.

Interested in more info about St. Joe? Click here to add it to My Watchlist.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.