There are a lot of studies on this.
Typically, it is not advised for short duration workouts (less than 90 minutes). If you are training longer than 2 hours, as you commonly do in endurance events, then I would advise it for performance. Otherwise, right now, I could not advise it for weight lifters training in short duration workouts. I am not going to be dogmatic about that, but based on my research, those are my current conclusions. I would love to hear others thoughts on the topic though (I know Vlad has done a lot of research/experimentation with this). That is subject to change as I investigate this topic further (a definite goal of mine in the near future).
You can read this post for some issues with that method, here.