While I will say the Splock is added insurance (not 100% guarantee), I still stand by my thoughts (as well as others), that a bolt capture does nothing.Easy, VTT even addressed this issue as well. So there is a gen 1 and gen 2 SPLOCK design. The Gen 1 had a spiraled spline design like a spline remover thread, this prevented the spline lock from biting into the crank fully in some cases and that's why some gen 1's slipped, there is also a discussion how a spiral spline will only bite tighter and work in one direction. I believe it was only one or two cases of it not working, which is extremely little. VTT addressed this issue by making the Gen 2 SPLOCK which has straight splines (now it works in both directions) and must be pressed into the crank, this means the splines already have bit into the crank upon installation and is guaranteed to have been locked in. They even confirmed it with images of the spline marks into the crank.