The scoring system. It sounds like a small thing until you realize it changes everything about how you approach a workout. Knowing that your warm-up, your recovery intervals, and even your rest days are being tracked and graded makes you show up differently. I stopped skipping the "boring" parts of sessions because they actually count now. The weekly leagues are the hook, competing on consistency rather than raw power means it's actually fair, and that keeps you coming back. Six months in and I've had my most consistent block of training ever. Nothing else has done that for me.