Andrew
Uhm... I think I was victm, again, of idiomatic barrier...
If we are talking about pull ups with own weight, horizontal over the ground, it is a good mark, but it is not an exaggeration for a boy.
I was thinking in lift your own weight holding on to an horizontal bar. Then, it is an absolute monster mark.
I am not big and I have good arms for a girl, and I can do 2/3 maximum, maybe 4.