Oh I will assume this is what you meant on your comment in my thread. My conclusion: You do not understand the manga.
Summoning Jutsu, while classified as ninjutsu works different than regular ninjutsu and has its own set of rules. All you need to summon is the blood of the caster and the hand placement on the summoning location. No hand seals are used except for when the original summoning takes place. If you want to argue that Orochimaru needs to direct his chakra flow to his hands, then that's what Orochimaru's summoning tattoo is for. Sasuke uses summoning tattoos as well with his weapons.
Orochimaru wanted Tsunade to heal the necrosis on his arms, and the rest of his soul would still be able to control the healed arms for mere Taijutsu. This is the same for his new body. Sarutobi really did a number on Orochimaru, and left him without Jutsu...Sasuke's victory over Orochimaru is because of Hiruzen.
This is the reason that Orochimaru can only use summoning techniques in the second arc; Triple Rashoumon and Hidden Striking Shadow Snakes are both summoning techniques.