I did the same sort of thing the other morning. Except it was inside and I just spaced out coming down the stairs. It is nice when your body does something automatically to protect yourself.
I imagine if you hadn't broke the fall the way you did you would be in much more pain.
I will admit to having wondered why we breakfall SOOO much in the fundamental class.
What we think, or what we know, or what we believe, is in the end, of little consequence. The only thing of consequence is what we do. -John Ruskin