[claudius]

I have no idea about axes in general, so please acquire a large piece of silicon dioxide before reading on.

That said, it seems that the problem with traditional axes is the large amount of friction from penetrating the wood. This requires a firm grip of the handle and long swings to induce sufficient kinetic energy in the head of the axe. With the rotational design, much less energy is needed, allowing for a) a loose grip of the handle and b) shorter swings, which in turn allow for better aim.

But, as ghshephard wrote, some additional/independent information might be very nice.

[miahi]

A firm grip on the handle as the axe hits the wood is a sure way to sore/strained wrists even for a normal axe, as the handle can rotate and also vibrate, depending on how and where it hits the wood. A loose grip looks like a must with this axe. Notice the handle is round for most of its length, to rotate easily. This is not usual for a normal axe, as the shape of the handle gives position feedback to the hands.

[StavrosK]

Silicon oxide? Take it with a grain of... quartz?

[graeham]

Sand. Probably meant a grain of sodium chloride! :)

[thaumasiotes]

Sand is silicon dioxide. Quartz is the same stuff. But if for whatever reason you have to acquire a "large piece"... quartz is much prettier ;)

[claudius]

My apologies :)