A thought that's currently knocking around my head goes as follows.

In order to cut, we must extend our arms. What is the timing of this extension.

It strike me there are four possibilities;
  1. The arms should be extending through the cut.
  2. The arms should hit maximum extension at the instant of contact.
  3. The arms should already be extended as the cut lands.
  4. It doesn't matter/You can mix it up.
Let start with option 1.

The arms should be extending through the cut.

I dislike this because it seems like a too simplistic approach to getting forward motion into the cut. A kind of obvious "pushing" that feels to me like it's weak.

We'll skip over option 2 for a moment and go to option 3.

The arms should already be extended as the cut lands.

It seems to me that this timing produces very a flat/dead feeling cut that lacks much of the dynamism evident in high level cutting.

Option 4.

It doesn't matter/You can mix it up.

As I discounted the points 1 and 3 I've effectively discounted this as well.

Which leaves me with the second option.

The arms should hit maximum extension at the instant of contact.

I like this. It seems to me that to have the arms hit maximum extension as an instant in time with the foot hitting to floor, wrists extending, etc.. would be the best way to have a powerful but dynamic cut.

Furthermore, while trying this out I've found it encourages me to do seme with my body, with little or no arm extension until I start my furikaburi. This feels more powerful than simply sticking my kensen out at my opponent face (as I'm otherwise apt to do).

Need to put lots of thought and sweat into this.