No you're not understanding lol. The whole point of me bringing up the bone premise is because we're talking about blockage of chakra. Chakra is blocked by solids. No where in the manga nor viz does it state Kidomaru's technique was SPECIALLY MADE to block chakra.You're still not understanding that it is still regular bone no matter how hard, which is what i said earlier. Kidomaru's technique is specially made to block chakra based attacks and is not bone. Meaning, an Hyuga could potentially penetrate and damage him from the inside with Jyuken. Gaara's technique is a pure crushing force, not a technique specifically designed to damage organs and shut down chakra points. Meaning if the armor is hard enough, they won't be crushed.
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All it does is create a solid exterior to block chakra. Simple.
Any type of technique with similar premises as Kidomaru's in that it prevents physical blockage for the user can block chakra-based techniques such as the Hyuga's Gentle Fist chakra distortion.
On top of Kimimaro's bones being much, much more durable than Kidomaru's own Golden Armor. Favoring him even more.