Couldn't find a definitive answer to this. If you succeed at a DC 15 soft fall from a mount, do you avoid being prone in addition to not taking any damage?
RAW is "Soft Fall: You negate damage when you fall off a mount. If you fail the Ride check, you take 1d6 points of damage and are prone. This usage does not take an action."
The wording seems to imply that you're only prone if you fail. To me, however, it seems logical that if you soft fall you do one of those rolling falls like you see in the movies when folks jump out of a moving car and are (miraculously!) uninjured. Thus, you're prone but undamaged. Also, if you don't end up prone, soft fall seems to overlap a lot with a quick dismount, which is a DC 20. If you need to quickly get off your mount, why not try a soft fall and if you make it you land on your feet and haven't used an action? The DC is easier than if you try a quick dismount.
Sounds right to me.
It looks like soft fall has an easier DC than fast dismount, but the penalties are harsher if you fail.
I guess the other things to ask are:
- Can you can intentionally fall in order to try for a soft fall? (I think yes, but I'm not sure)
- If you can, is it a free action? (If not then the point is kind of moot)
I mean... To my memory of falling, you're only prone if you take damage. So if you succeed the soft fall DC, you wouldn't be prone.
That said, soft fall specifies "when you fall". So to initiate it yourself you would need to move to dismount anyway (ending your move action not on solid ground). It seems more like a "you can use Ride instead of Acrobatics to avoid the fall".