If destroying the chakra points makes it so that Edo ninjas can't repair themselves than they aren't as strong as everyone has thought.
A clean hit rasenshuriken should be able to take out any Edo ninja by destroying their chakra points.
Obviously the reasoning used by Hashirama contradicts the manga. All you woud have to do is destroy parts ot the edo ninja's body and with the chakra points being destroyed with them that part of the body shouldn't recover.
It is a plot hole.
Hashirama didn't state some of the points were destroyed though, but all of them. Furthermore both he and Tobirama are chock full of them, much like Nagato. Naruto was different when pein put them in him because the rods were smaller, way fewer in number and he possessed Kurama's massive chakra. Same thing with the jinichurikis/bijuus having them because they only had one small hidden one.
Based on these observations, I'd say using a barrage of gigantic ones is probably much more dangerous and potent compared to one or a few small ones since the chakra would probably be greater in volume and concentrated, thus it would be dangerous to touch and would be powerful enough to absorb all or most of the do tensei chakra, preventing it from regenerating. Naruto and Hinata could probably break them due to their high physical chakras and physical strength. Naruto is Ashura's reincarnation after all with Yang Kurama while Hinata possesses the Byakugan once wielded by Kaguya herself.
It's never exactly been revealed what the black rods are, but I'd say they are probably condensed and petrified chakra left behind by the juubi in the gidou mazou. The nine dragon spirits' power inside the mazou, which Akatsuki used to suck up the bijuus from their jinchurikis also reflects this ability, as well as the shinju, implying it must be very powerful.
Those are my thoughts.
