But Mū wasn't able to spam, even use, Jinton after Fission Jutsu. Edos cannot spam their attacks, apparently.
The only reason Mu could replicate jinton after fission was because by splitting himself he split his chakra in half allowing each body to have a equal half. By splittig himself his chakra reserves dropped under what was needed for him to create a jinton.
Heres a example of what I mean:
Mu = 100% chakra
Jinton requirement = 55% chakra
Mu Fissions
Mu 1 = 50% chakra
Mu 2 = 50% chakra
niether had a large enough chakra reserve after the split to activate jinton.
He still could replinish his chakra reserves, its just that after the split his reserves were lowered.
All edo's have unlimited chakra. Mu was justu to only idiot to split his chakra to retrict his from using heavy chakra taxing techniques.
Mu