> 99.99999+% of newborns have 2 hands, 2 legs, and 1 head
This number is far too high. The rate of conjoined twins (violating "1 head") is about 1 in 50,000 [1], and the rate of "limb reduction defects" (violating "2 hands and 2 legs") is about 1 in 1,900 [2].
Those correspond to 99.998% and 99.94% respectively. 3-4 nines is still impressive for such a complex system, but let's not claim it's 7+ nines.
This number is far too high. The rate of conjoined twins (violating "1 head") is about 1 in 50,000 [1], and the rate of "limb reduction defects" (violating "2 hands and 2 legs") is about 1 in 1,900 [2].
Those correspond to 99.998% and 99.94% respectively. 3-4 nines is still impressive for such a complex system, but let's not claim it's 7+ nines.
[1] https://www.chop.edu/conditions-diseases/conjoined-twins [2] https://www.cdc.gov/ncbddd/birthdefects/ul-limbreductiondefe...