Quote Originally Posted by Azonalanthious View Post
I don't recall exactly how the technique was described, but if it represented a semi-permanent reduction in power (you didn't get the power back until the technique was released or destroyed), I could see that being enough of a draw back to limit the amount highly paranoid villain types would be willing to use it -- don't ever want to leave yourself weakened much if you can avoid it, "just in case" after all.
I don't remember there being a cap on the technique, but both Itachi and Kisame were meditating while the technique was active, leaving your real body vulnerable. I'm unsure whether the clone simply has 30% of your chakra limit, or if you actually have to put 30% in - and that would also effect your combat readiness when you wake up.