Usually when I ask myself “am I over thinking this” the answer is always “Yes!” haha.
Have you done the Stomp walk yet? I can’t remember if I have seen it or not.
This one is just a little more complicated because the feet stick on the ground (when planted) and the torso moves forward. There is several ways to figure out the distance, and there can be a little back and forth until you have it working nicely (expect to get it a little wrong the first few times – but then you will figure it out.)
The easiest way for you to get your head around it might be to work backwards from the passing position to the contact. That will be half a cycle (6 frames – a walk is usually around 12 frames per step). The Torso should be linear so once you know how far the distance it moves over this 6 frames, you can then calculate it over any amount of frames. The back and forth will come when you realise that the leg can’t stretch that far backward as you need it to which means your step has to be slightly smaller.
But all these things are part of your learning. Making mistakes and learning from them makes you better at animation….as long as you learn from the mistakes that is haha.
Hope that helps.