Pressing Snatch Balance was something I got from the Burgener Warmup or Greg's book or the website. Can't remember. I've only used them with stick or bar I think, maybe some light weight on the bar for warming up snatch balances (dropping and the heaving kind).
I got the idea of just neck jerks because I was at an affiliate recently and they were trying to go over with it from a front rack with PVC. Some people it seems can get into a good front rack with PVC, but not me. Anyways, it just looked like ass really and that it would be SOOOO much easier from the neck. A lot of the people were having hard enough times with the rack as it is, the ones who weren't flexible.
From the neck would make sense for either the power or split. Obviously with the split, you'd have to go over footwork and probably start with the bar/stick overhead anyways.