@LiquidFeet
So here's a question...
If you do an extend to release turn your new outside leg is already long and it's easy to let the pressure build throughout the new turn without pushing off.
If you do a retraction turn both legs are already flexed but the outside leg needs to get longer as the new turn progresses, how is that done without pushing or just parking?
If you do nothing but flex the new inside leg (while tipping the ankle inside the boot), that new outside leg will naturally extend enough to keep the ski on the snow as your body crosses the skis into the next turn. This natural extension, not a push, just happens all by itself, otherwise you'd be doing a white pass turn, a very nice one in fact. It takes conscious effort to keep that ski off the snow, but no conscious effort to keep keep down there where it belongs.
And the pressure just comes to that ski depending on the accumulating forces. No push is necessary for that.
But then, as Ozon accurately surmised, if you are going so slow your momentum doesn't move the body across the skis with the amount of oomph you want, you can extend that new outside leg after flexing the new inside, in order to provide a little push, just the right amount.
Play around with this; no extension, little bit extension, little bit more extension. Be careful using a big mother extension after the flexing. You might use up what's possible and then be in park before the fall line. I did this once in creamy March snow, and my skis folded under me. I ended up in the woods sitting upright against a big boulder. Big end of season injury. Ask a slalom racer about a strong extension after flexing, not me.
Avoid parking after a flexion release by continuing to shorten the inside leg while tipping its ankle until you get to the fall line, then begin the next turn with a release.
And when you succeed in getting your hip all the way down (which I have not done), I'd trust Paul Lorenz and do a little extension to jump start the flexion release: