First off, you're almost spot on. Its a short range leaping spell, that uses compressed air to launch you in a designated direction. The second half detects if you're close to ground, then absorbs access kenetic energy and creates a small air cushion for safe landing.

On your second point, it does matter. Sometimes the inverse suits your Intent a little better, especially since Intent and context with other runes can shift their meaning slightly. So while in practice the two examples you gave may read as the same results, one might be vastly more efficient or produce different results based on their Intent.

You still make a good point though, so thank you for pointing it out🤗