b) he is not as strong as Kimi (kimi broke through all of his defences)
kimimaro's thickest bone didnt get past the Saikou Zettai Bougyo Shukaku No Tate (Supreme Absolute Defense, Shield of Shukaku)...it shattered kimimaros bone..
yeah im just thinking gaara has never been scratched before...but 3 genins could get past his defenses and punch him around a bit..