Notes
We ran 1.5 WU, 12 400s with 400 recoveries between, then 1.5 mile CD. The 400s were around 1:30. The fastest that I know of was at 1:25. Several were sub 1:30, especially the latter half.
The recoveries got slower and slower and eventually we started walking a large portion of the recovery.
This was a HARD workout.