As we mentioned at the outset, this isn’t a Genesis tutorial. Rather it’s an introduction to Genesis for strangers. The basic thing a stranger needs to understand about Genesis is this: know Genesis’s action and filter hooks, and everything is yours to control.
David Hayes has a great post on WPShout that explains Genesis, by StudioPress, and it's origins (I can hardly contain myself right now) as an early WordPress theme framework. It can help understand why Genesis does what it does.
I don't know many consultants who haven't had a lead at some point contingent on knowing the Genesis theme. And this is the post you need to get introduced, conceptually, to Genesis the theme and Genesis the community.