The falling skill is not a reflex, it is a learned, habituated thing, but it does take into account (work with instead of against) true reflexes that take place when we slip or stumble.
Everything is all status quo from our body's pov, then something disrupts us (stimulus) and a bunch of reflexes happen (postural righting, extension, crossed-extensor, metatarsal kick, etc...) and while the reflexes are happening and we are beginning to fall, our mind has time to catch up to what is happening and guide the fall enough to minimize the consequences.
So, yes, the skill part of it is responsive instead of reflexive, as Rick pointed out in the last post. But the response is based upon, and works in harmony with reflex to the extent possible.
That is reflexive falling skill.