LOgic is missing again.

[Emperor]

it takes along time to build up the chakra for it, but once you get the chakra built up then you can sort of use it istantanously.

by the time kakashi had enough built up enough he only had enough chakra to use it twice, once to take out the nail, and the other time to take out the missile. and it sort of still took some time(the nail took less time because it was small) but it still took a little of time to take out the missile. and like the other guy said there was the other body as well.

yaahhhh....
i think it foolows the laws of physics
more mass = more energy

 

[YaminoSoul]

1. Space time is the fastest jutsu ever made right.
2. Kakashi can use space/time jutsu.
3. Kakashi can use it very fast and precise even on the fast moving objects.
4. That jutsu sucks anything in the other dimension, no matter what it is: part of the body, nail, hand.
5. Targeted on pain, it could suck him ( or his head) in the other dimension.
6. Kakashi can store his chakra in konoha. Means he can use that jutsu 2x. 2x3 = 6 times.
7. Pain has 6 bodies.
8 Conclusion ? Why waste chakra using raikiri and other useless moves ? He could just stand and kill pain from the distance lol. Thats how it is. Kishimoto needs to think before he develops jutsu's. <--- IMO.

Yes, but that doen't garantuee it can be prevented. Also kakash?'s very limited on chakra, and it's slow, he can't just absorb a pein because there are multiple and they're nearby. He will only lose unneccesary chakra.