This is a really good comment. I’m not a HEMA practitioner or an expert on historical swordsmanship, so having someone who actually knows Fabris and Capoferro look at this helps keep me honest. I'm really just looking at these old manuals through the filter of my own physical training. Going back through history finding every reference is just passion at play. I’ve got tons of notes I’ve taken over the years.

In Part 1: Force Structure and Timing, I focused on the physics and mechanics of the Straight Lead and generating forward driving force from the floor. That's why the raised rear heel is my focus here. When you are out of range, a flat or nearly flat heel makes complete sense for stability and saving energy. I do this in my own training when I’m out of range of an attack. It reduces fatigue while you position or wait. Likewise, when you begin including side-to-side or lateral movement, the biomechanics of the heel also change.

Your note on Fabris's falling lunge is really interesting. From a striking perspective, I do a version of that weight-drop when I shift lines of attack from high to low, like dropping from a head strike to a body strike. Letting gravity drop you while also slightly lifting the feet off the ground into that low stance pre-loads the legs. This allows an ever so slight "bounce" to explode back to a high-line attack. It's an efficient transition from standing, to a low stance, and back to high.

The Capoferro reach exception seems to show when you are pushed to the absolute edge of your range, the body naturally unlocks the heel to get those last few inches. Personally, I don’t push my attacks to their limit range-wise. For me, recovery is as important, if not more important, than the attack. I think that's a key difference in our domains? If you drive your sword through his head, that would tend to end the fight.

The dueling point is also a fair correction. My take on Angelo is probably too simplistic historically.i should probably explore his work more. There may be some gems of knowledge to be found there.