I asked my dad about the Ruf levels and he said that I fell in 3/4 for much of my first year or two but I just accelerated once I got into preschool and no one knew what to do with me by 3rd grade. I know that I was 4/5 by that time based upon what I was reading and doing. My IQ is higher than the one Ruf listed for 4/5.
Mr W has most of the 4/5 Ruf milestones - but in some ways he is very unique - such as his musical affinity and observation skills and his good cheer - all of which astonish me, yet no where is this mentioned. I also think he knows A LOT more than he lets on. He is his own man and not a pet monkey.
Looking at the bios of people like Feynman - he was clearly 5 given his behavior, but he has said his IQ tested in the 120s.