> 1. We use Lf/Rt arrows to move the cursor, don't we? Then use Up/Dn to do > the same kind of task is symmetric, and thus more reasonable.
you're assuming the task is symmetric; perhaps left/right and up/down aren't analogous, because x movement in a fixed y (left/right) is not the same as y movement for varying x (up/down without fixed-length lines).
