It all depends on your quest. If losing weight is the goal it may not be as conducive to positive results since a deficit in calories is the quest. If the quest is increasing the capacity of the cardio system at task is the time of recovery from my understanding. How long when at an raised optimal pulse rate vs. how long before complete recovery occurs is the quest. It may not be 'easily' measurable offering a known result with short intervals. if the quest is getting your recommended one hour a day at a raised heart pulse it works just fine. The heart will respond to the condition of stress and recover.
Again, it all depends on the quest.