Not a bad association. ;)
I think the name is a bit heavy, though. Personally, I would probably nickname a little
Jethro as Jeth or
Jett, which I feel seems more appropriate for a little boy. Of course, once he's an adult, he'll be able to pull off
Jethro, but Jeth or
Jett would probably still feel a little more smooth, so he (and others) might stick with that instead.