This is my favorite PV drill on the rings, as demonstrated by "Amy" ...
http://ca.youtube.com/watch?v=Gn5LIiHmP ... re=relatedFocus on the downswing part of this drill.
IMO, she extends too far past the upswing, into a feeble attempt at an extension. That's not the important part of this drill. It's the DOWNswing!
My second favorite - if you have the space to do this - is to do this same swing (but not so exaggerated, of course), from a running start. For this drill, it's actually better to have a SHORTER length of cabling to hang the rings from. This is because it gives you more of a 'jolt' that simulates the pole hitting the box. With a LONGER (normal) length of cabling above the rings, you'll swing too far out, without ever hitting the point at which you feel any jolt. I hung a pair of rings on a tree at home for this.
If you're stuck with the long, normal-length straps/cabling, the way to modify this (and this isn't really advice for Sooch, but more for intermediates and elites) is to attach a couple more cables (could even be bungees - if strong enough) to just above the rings, and fasten them down to the floor or wall such that they'll stop the swing of the rings as you run up and catch them.
Not allowed to modify any rigging at your school? Then just have a buddy on each side of your runup hold these ropes (that are attached just above the rings) firm. They'll give you the jolt you're looking for!
This is the way the rings can work almost the same way as the "hinge/whip drill from a running start" on the highbar. In fact, it's an improvement over that drill for 2 reasons: (a) because you can set the height of the rings to whatever you want; and (b) because there's no issue re how to grip the highbar. You just grab the rings after your takeoff, and they twist in your hands in whatever position feels natural.
One nice thing about rings is that by raising them to any height you want, you can swing so that your trail leg just misses the mat on the floor. You can also raise them quite high up - to practice JUMPING up on takeoff. You can't do this on a highbar - they're rigid, and set at a height ideal for [short] gymnasts. This is usually too low for anyone over 5-10 or so - especially if the bar dips during the drill.
Also, here's some skin-the-cats that Amy does on the rings:
http://ca.youtube.com/watch?v=D9MiJlGPC8Y&NR=1 - good for general body awareness on the pole, and for conditioning the muscles to become accustomed to being suspended on the pole.
Kirk