Sasuke: Having EMS means that most likely he can use amatirasu bigger than the scale of the 8 tails. If he fights along with Tobi he can burn Gedo Mazo (Although it would take time) with amaturasu, while the others keep Tobi busy.
Itachi: Having MS means he most likely will not be able to use a huge scale amaturasu like sasuke. (Although very possible with his high chakra reserves and mastery over chakra). What Itachi can mostly be effective for is sealing the Gedo Mazo. As we all know the thing is currently struggling so he can stab it and then its gone, or 8 tails can pin or hold it enough for it be pierced. Totska blade immobilizes the moment it pierces so its game over when it does pierce. Tobi can be kept busy by naruto in the meantime to the point were if he materializes he may be injured. Very possible scenario when Itachi is present.
Note: There is a reason why Itachi was killed off. He would simply make Tobis fight an easy win when you put his intellectual ability with his one shot techniques.:ice:
Itachi: Having MS means he most likely will not be able to use a huge scale amaturasu like sasuke. (Although very possible with his high chakra reserves and mastery over chakra). What Itachi can mostly be effective for is sealing the Gedo Mazo. As we all know the thing is currently struggling so he can stab it and then its gone, or 8 tails can pin or hold it enough for it be pierced. Totska blade immobilizes the moment it pierces so its game over when it does pierce. Tobi can be kept busy by naruto in the meantime to the point were if he materializes he may be injured. Very possible scenario when Itachi is present.
Note: There is a reason why Itachi was killed off. He would simply make Tobis fight an easy win when you put his intellectual ability with his one shot techniques.:ice: