Tuesday: I slogged my way through 4.59 miles by necessity. I started having the same sharp outer knee pain at about 2 miles. It was an out-and-back so I walked off and on to make it back home. Later I did a little google-based research. I think it's the illiotibial band where it connects to my tibia. Some sources say it can be caused by overpronation. I remember one time at Fleet Feet the guy showed me on the video that my left foot slightly overpronates. I'll take a few days off to rest and then use my stability shoes to see if this corrects the problem.
Saturday: 3.5 miles. After doing research, I wondered if ITB pain was caused by running in cushioned rather than stability shoes. I took a few days off and ran today in 903s (stability). Although they lack the cushioning I'd like, I didn't have any knee/ITB pain. Maybe I'll just buy some cushiony insoles and demote the Asics Cumulus to non-running uses...
Days run this week: 2
Miles run this week: 8.09
Goal for next week: Follow week 9 of the Hal Higdon half marathon training program (adjust if knee pain persists.)