Working on my Zornhau: getting worse before getting better

As I've mentioned before, I regard myself as having an adequate technical knowledge of the Zornhau [Oberhau from right shoulder] and understand what aspect of it I'm trying to improve: maximum arm extension (without locking the elbows) to give the cut just a little more range. So, over the last few days I've been working on just that. Or so I thought. Yesterday I was very frustrated because it seemed as though my Zornhau was getting considerably worse: beyond the fact that I was lacking that satisfying fsst as the blade sweeps through the air (probably a sign that my edge alignment sucked), the tip of the weapon was travelling in a distressingly wobbly line. This wasn't only happening during fast cuts, but also when I cut slowly.

The only thing to do was go back to the basics: forget full extension, forget adjusting my grip on the hilt (which I realized I was also giving a little too much thought to, after being reprimanded by my teacher to stop opening & closing my hands while in vom Tag), and just cut. "Punch" with the right arm, "kick" with the right foot to swing the hip. I simplified it further, by using a one-handed grip on the sword to eliminate any possible interference from my left hand. After a while, I began to notice a slight improvement. Satisfied that at least I wasn't getting worse any more, I moved on with the rest of my practice. This morning, I practiced it the same way, stripping the cut down to just the things that make it a cut. We'll see where my cut is next week; maybe I'll still need to extend a bit more, or make some other small adjustments, but for now, I'm letting that stuff go.

EDIT: After some discussion with the teacher, apparently the "punch" mechanic is obsolete for our purposes. Back to the drawing board with this one. I'm just looking for consistently good results here.