It seems lots of letsrunners only consider a workout a quality workout if you leave gutted and DEVASTATED.
Pros like Nick do easy workouts to prepare. If you're a guy like Nick (not a 800M/Miler but a pure 800M guy) a easy day would look just like what he did.
Try adding some "easy" workouts to your training. Save the truly hard effort for a handful of workouts later in the season when you are in good shape.