OK, if this is a contest to explain the rolling hone to Chris, here's my entry.

Imagine a super-smiling razor. So extremely smiley in fact that the blade profile is a half-circle. It helps also to picture it as a true wedge. Now lay that imaginary blade on a hone. It doesn't sit flat. The heel and toe taper away, and the middle part is thicker, so it rocks back and forth on this 'hull'.

That's all – you're just rolling it on its hull as it moves down the hone.