There is not a huge difference between speed-endurance/special endurance I and intensive tempo. Generally I don’t think there is any difference between the two for sprinters with the exception being intensive tempo is more a fitness conditioning concept around pace management while speed and special endurance I are more about modeling the specific race distribution of energy. Thus the biggest difference between them comes down to intensity of the acceleration phase and rest required because of the acceleration intensity + the intensity of the rest of run….
Isn’t improving Speed End, at least in some large part, training the neuromuscular system to function at maximum capacity (MaxV) for as long as possible? I’m not sure this can be accomplished with intensive tempo. And since there are limited number of training days and much of a sprinters training empties the CNS tank, it may be more an issue of IT (which does not improve Max V as well as >90-95% flying sprints nor does it improve speed endurance as well as >90% long sprints) competing for the limited resource and impeding the progress that could be better served with a short sprint training plan centered around accel, max V, speed end and ET for recovery.