The pivot heel is just an outdated design that can be done beter using different techniques. It's a good design and is very functional, but now there are definately beter ways to make a binding that is safe, and has appropriate hold. The way i see this binding evolving is evenutaly into something like the line binding without the plate since with the newly designed heelpiece the boot could release lateraly using the toe as a pivot, with some small modifications of course. That design would have been impossible with the pivot heelpiece since the bars on the side "cup" your boot in and wouldnt allow it to release in that direction. Also the pivot heel always had shitty forward pressure and always had a problem of sliding back on the track if you were a burlier skiier.