Being you're aware of the guide, posts like this go --- you guessed it --- in the guide. That being said, I will answer and then close this thread.
1. It's softmodded, trust me.
2. Because we have you do things in steps/chapters. You don't need to backup the SD card (in terms that you're supposed to have a blank[ed] one to start with. The third time you don't delete it after completing the guide, you leave it as-is.