I realize we're all just speculating here, but I still wonder why the article mentions the workout in this context:
"Returning home recently to Tucson, Lagat said, he did a series of track intervals: two and a half miles in 11:54, a three-minute rest, a mile and a half in 7:14, another three-minute rest, and a mile in 4:38.
"'It tells me from the workouts I’m doing that I’m strong and I’m fast,” Lagat said."
How does that particular workout tell him that he's strong and fast? For a guy who can run sub-13, that would seem to be a fairly light threshold workout with generous rest periods. I'm not saying that it's a bad or inappropriate workout for Lagat or anyone else, but it still seems odd that it would be discussed in that manner and context, as though it says something about his current fitness level.