Speed endurance or ??

Was thinking of a speed endurance session for a 400m.
400m divide into 60m is 6.66 efforts, or lets say 7.
a Goal time of 44sec
44s divide by 6.66 efforts = 6.61sec for a 60m

therfore the session am thinking

flying 60s
7x60m with 10min recovery
once that is acheived
drop 30sec off the recovery
until that is acheived
continue this untill basically a slow up at the end, slow turn around and continue.
Training that slowly mimics Racing at goal race speed.