Lets not forget when almight push is used that there's a 5 sec Gap after itachi would find a way to get'em ,i thought about that to but i don't think he's able to absorb that attack if he could of i honestly think he would of instead of using almight pushHe could of shinra'd it off or absorbed it from the get go, and maybe not a Chibaku Tensei but a Shinra Tensei because Nagato is able to sense when he is about to use it.