The pre-flood people lived so long because 1)they were the first descendants of Adam and Eve, who had nearly perfect DNA, 2)the earth was shielded from the suns harmful cosmic rays. Also the “decimal theory” doesn’t hold water because if you look at the ages of Noah’s descendants you sill find that each generation lived fewer and fewer years until their lifespans were no longer than they are today.
I wasn’t able to connect to the link, so I don’t know what the “decimal theory” is, but in today’s edition of Pookie’s toons, one of Mallard Fillmore’s predictions for 2016 that Donald Trump will attack the decimal system.