I started off my speedwork like such a stud - my first sub 6 mile!! 5:54, actually. Then I crossed the street and did an 800 (2:47). That is my AW.
But then I am subtracting half of that because I turned around to do the same thing back and realized that I had a nice tail wind that whole time. I was much much less of a stud with a stupid headwind.
Its crazy how much a little tailwind can help you and how much it can hurt you. If I am supposed to ride my bike, and I see wind, I dont even bother, lol.