I'm no rock star, but what I like about sport leading is that I actually learn the limits of the possible (and it's way above what I thought I was capable of at times). I feel like I'm about to grease off, make a desperate lunge for an improbable hold, and stick it. That is such a great feeling. Call me a headcase, but it's something I have trouble doing on trad lead. I'll back down to my last piece and cogitate. Learning just how long you actually can hang it out there makes it easier in the trad realm too (at least for me). You learn a lot when you go to total failure and your hands just open up off the hold (rather than your brain saying "no way I'm trying that")