Well maybe since they each have to do equal amount of tasks when they get to a task and the old man thinks he can do it he does. That way they dont get in a pinch where the old man has to do something he might have a hard time doing,costing them alot of time.
I dont think they kid is lazy, if you notice he carries his grandfathers bag pretty much all the time.
chinese grandad is like a human fortune cookie that works a little too hard at it...But you have to root for him, he got a hernia the first show
oh, and as far as the show in 2 weeks..
it looks like the go to italy, and the fast forward they teases for the grandpa and son is some kind of absurd art sculputre they have to do...You can read Fabro in the place they are in. His is an italian sculpture who interestingly enough appears to have died shortly after this was maybe filmed...or i am all wrong http://en.wikipedia.org/wiki/Luciano_Fabro