In my mund the arrow should still penetrate to its full potential. This is of coarse assuming the bow is properly tuned in the first place. Now where it strikes the moving animal will effect the penetration depending on what is hit. As for the disks most times we see them shot out of the air is with a traditional bow which will have less energy than a modern compound there fore less penetration.
Tuning is the key if the arrow is fishtailing it will not transfer its energy for penetration. This is why many archers bad mouth many very good open on impact broadheads. Many use them instead of tuning which can be a chore sometimes. When done though you should be able to shoot fixed blade heads open on impact heads and field points to the same or very close to same spot. This is without moving your sights. This is just my theory and I may be wrong so I look forward to what others have to say.