It was just an excuse to give Sasuke Hashirama's chakra :| we still don't know the jutsu
Don't think it was even a Jutsu.
Then read again :|
Wasnt it a binding Jutsu for Madara
Remember how Madara made Sasuke freeze in the air while Madara just stabbed em.
Or it was just Chakra so Kishi could set up the Rinnegan for em