I've always been told to stretch before workouts or running. I started questioning this practice when I began running with more experienced runners who would stretch after getting loosened up running a few miles. Now, I question the benefit of the practice at all.
When my knees started giving me problems, I noticed that I could instantly precipitate knee pain by doing the following: stretching. Me being the curious fellow that I am, I stopped stretching all together just to see would happen. Oddly enough, I didn't crumple up into fetal position and perish like I had been led to believe as a gullible PE student. Overall, my pain decreased, as a matter of fact.
Now I'm not going to make outlandish claims and say that stretching is worthless and no one should ever do it. I might even stretch some now and again. But I think we seriously need to question the "stretching prevents injuries" paradigm that we are all familiar with, especially in light of studies like this, which are not a few. In short, don't fear the reaper when it comes to running without stretching.