Once edo tensei was released their souls/spirits didn’t instantly go to Naruto 689 the impure world. After edo tensei was released, Dan like Obito, Used a jutsu, Reika no jutsu to control his ascending spirit to go to Tsunade.Then we have Madara who was in the same position as Dan who’s spirit was no longer bound to edo tensei and unlike Dan and Obito who used Jutsu to move their souls around, Madara returned his soul to his body to finish off Tsunade. The other souls moved on to the impure world and he was still bound to his edo tensei body “Before” he released the edo tensei contract.
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Then there’s the fact that Madara was dead for days and his soul should of already crossed to the impure world but Izanagi was able to revive him? Black zetsu Stated the Mangekyou Sharingan can acquire and learn techniques outside time so with that being stated that shows that what Obito did was not an ass pull and what he did was consistent to what Kishi stated in previous chapters of the manga.
I would go on further and use Orochimaru, Minato and Kushina as examples but i want to tackle the Perfect susanoo argument.
The requirement for Perfect Susanoo is having MS, No where was it stated you had to have EMS. When Madara showed his perfect susanoo it looks exactly the same as Itachis and Sasuke’s The only difference is that Madara stabilized his chakra and gave his a humanoid form. Onoki stated Madara Stabilized the chakra so to me that means the complete version is still perfect susanoo. It seems the amount of chakra the user has determines the size of susanoo and once stabilized it takes human form.