I have a few. First while in training at hunter mtn for a PSIA clinic. The drill was to stand on your skis and visualize you have on tennis sneakers, no bindings and you need to stay on the top of your skis. This changed my life. I ski in amazing balance, it's the core of my method. Second, is again some clinic along the way, maybe at mt snow. The clinician said " when do you start to stand on your new edge". Basically super early as soon as you finish with that old turn and you switch feet. Sound simple right. But that day I never looked back. From then on I practiced moving. Then third from my own discovery I learned to actually push that outside ski hard down onto the ice. Yup you need to stand on the outside new edge foot right under the hip and push! Hard if you want. Whala! I learned to carve super well. Four, then that's about it, uphill hand. Gain control over that sucker and your gold. Major upperbody stability. Insane.
So that's my bag. Sneakers, transition early, balanced pressure and up hill hand.
Totally changed my life. I'll never forget those four ah ha moments. Yah I know it's pretty much the entire BERP array.
Anyhow. I'm looking forward to hearing your moments.