One of the great things about this program is that no two workouts are exactly the same. You'll learn some new moves, hit your muscles in different ways, and never get bored. Despite the variety, there's one thing you can always be sure the workouts will provide: results. Do the work and good things will come.
As best you can, do the workouts as programmed. If you skip lifts, that means you're ignoring muscles that probably need some attention. Opt out of those deadlifts or back extensions and your lower back will be starved of important work! You can always use our Exercise Database to find suitable alternative movements if you're unable to a particular exercise.