Hey Richard!
Once again, keep up the good work!
http://www.youtube.com/watch?v=r1Hc9E5uA1kRound Stroke
This one really should be a continuous motion that starts in Ochs in one side or the other and ends in the same spot from which it started. One "Round Strike" actually hits twice....or at least potentially hits twice. That's what makes it "Round." Just doing a backhand strike and then withdrawing the weapon and stepping back isn't "round." The purpose of making it "round" is to build up momentum and make the strike more powerful. When you "double" the strike, it potentially hits 3 times and ends up in the Ochs position on the side opposite of where it started.
http://www.youtube.com/watch?v=QHB4xrbQaJINeck Cut
Of course the neck cut is simply any cut aimed at the neck. But of note here is that in describing this cut Meyer sets it up with a Krumphaw (even though he doesn't name the Krumphaw). So that initial action should decisively strike over the opponent's blade and "smother" it. The idea with the Krumphaw is that when used properly the opponent has no options and you have him! It works the same way with the Longsword. From the Krumphaw the Halshaw is a fast and powerful draw cut through the throat directly from the Krump position.
More Experimentation with footwork
http://www.youtube.com/watch?v=ZZ2UIL6_B_0I'm not convinced that Meyer used that "step-slide" as is seen in sport fencing. It doesn't really seem to be part of the Bolognese tradition, and we know Meyer's Sidesword has an Italian influence as Steve mentioned. So everywhere you see this "step-slide" I would do the "gather step" or what Steve referred to as a "Chasing step."
In paragragh 1.24R: Meyer notes 3 chief forms of stepping:
1. back and forward, toward and away from the opponent
It is unclear whether he means a passing step, a gather step, or both. One could put the the step-slide in here as well. But for me, the gather step just works better and is in tune with what the Bolognese Masters taught.
2. to the sides, described by the triangle:
“stand in a straight line with your right foot before your opponent and step with your left behind your right toward his left, this is the single. The other is a double step: step as before with your right foot toward his left, follow then with your left behind the right toward his left somewhat to the side, and then thirdly with the right again to his left.”
3. the broken or stolen steps, which are done thus: “act as if you intend to step forward with the one foot, and before you set it down, step backwards with it behind the other foot. Since these properly belong to the rapier, I will save it for there.”
Meyer goes on to say (Forgeng translation):
“Some might here be astonished, and particularly those who were inexperienced in combat, that I offer instruction about stepping; they might believe that nothing much depends on how one steps, or even if something depended on it, that ‘The marketplace will teach it to you well enough’ (as the saying goes). But so much depends on this, that as experience shows, all combat happens vainly, no matter how artful it is, if the steps for it are not executed correctly. Therefore the combat masters of old who were very learned and experienced in this, stated in their twelve rules: ‘Whoever first steps after the cuts should not rejoice much of his skill’.”
Here Meyer emphasizes the importance of foot work and his comments reflect the fact that it is seldom discussed in prior written works. Yet he himself has relatively little to say about it and does not describe his stepping methods in very much detail at all. Its a bit frustrating!

I should also point out that some other footwork does show up in his Sidesword chapter that he didn't mention previously. One is the leg slip, which you showed as part of the "hand cut." The other is what Meyer called a "Broad Step." I think this is essentially the same thing as the "accrescimento" from the Bolognese method. Its not really a "lunge" proper, but was likely the precursor to it.
Keith P. Myers
Lifetime Member HEMA Alliance
Affiliate: Bartitsu Society & Cateran Society
Friend: Meyer Frei Fechter Guild
Rockville, Maryland