I second this. While I'm not a powerlifter, I do lift regularly. Two years ago I stretched before doing anything, including a warm up. Sometimes I would be in a rush and skip the stretching. After I noticed that it made no noticeable difference, I dropped it and just did my regular warm up (run a mile). Now, before doing anything really heavy, I'll just do the movement with little weight or only body weight. I've been able to lift more and seem to have less muscle fatigue as a result.