This program only spells success if you stay determined and ready to hit the weight every time you walk in. Keep your nose to the grindstone, and you'll reap the benefits.
You may be tired and looking forward to a lower-volume workout, but that doesn't give you an excuse to skip any of the exercises or sets. The GHD and crunch superset at the end of the workout is meant to help you build stronger glutes and a stronger core. You'll need both to become a better squatter.