I think a main goal is cns recovery, and tempo running I believe (at slower speeds) is the training form of active recovery. Just keep it on the grass and the impact problem is minimized.
I don’t think tempo helps to recover faster from CNS fatique. In my opinion, the main purpose of tempo would be maintain/improve fitness level. If for many tempo is an active recovery, so why in some cases not jogging (if really feeling sore or having heavy leg feeling)at almost walking speed for 15-25min and recovering even faster before next quality session?
But also, how are you going to run reps of speed endurance/special endurance runs, if you don’t have adequate aerobic capacity? How will you be able to go through multiple rounds at a multi day meet if you aren’t properly conditioned?
How much aerobic capacity power athlete needs to start speed endurance/special endurance runs? I agree that first 3-6 weeks would be geared more towards conditioning. How much aerobic capacity an athlete needs to go through multiple rounds at a multi day meet?