What does that have to do with this? Explain. Not sure if you're making an argument point or being rude if you don't explain.
reason over feats
does it make sense for a giant shuriken thrown with enough force to fly to only slightly Pierce the back of someone? even then, does it make sense for that someone to not be immediately paralysed from the spinal injury and weight of the metal?
just as i find it nonsensical that Zabuza doesnt know how the Sharingan works when Kakashi is already world famous for copying jutsu with it etc, i find Iruka survival of the giant shuriken to be nonsensical