At every wine tasting that I have been to, without exception, there has been someone who swirled wine in their glass, looked at it, and said "wow- look at the legs!" For the uninitiated, the "legs" or the "tears" are the droplets of wine that run down the glass after you swirl it, it sheets on the glass, then forms into droplets. I don't want to say that the legs cannot tell you anything about the wine. Under the right circumstances, they can. However, at a wine tasting at your average liquor store, with some dude that is just spouting something he heard another "expert" say, it's highly unlikely. In that instance, the legs most likely tell you how clean the glass is, and what kind of detergent the store used in washing it.
In a perfect setting, a fuller, more developed tear is an indication of higher alcohol. At Shop-n-Save, it's an indication of someone just talking.