A childhood belief about songs

You know that song 'Heven is a Halfpipe' that goes:

'If I die before I wake
At least in heaven, I can skate,
'Cos right now on earth, I can't do jack,
Without the man upon my back.'

I was only little when I first heard it, and my friend and I had started to learn to skateboard. We were very confused by the last couple of lyrics in the chorus, but in the end, we decided that 'Jack' was a trick that we hadn't heard of, and this guy was really crap at it, and had to have the inventor of the trick on his back, telling him what to do all the time, and in heaven, he'd be able to do 'Jack' perfectly.

I'm forteen now, and I only realised the other day!