Does it? Seems pretty clear from 803.01.B
B. A player is not allowed to move any obstacle on the course, with the following exceptions:
1. A player may move casual obstacles that are on the playing surface where a supporting point may be placed when taking a stance. A casual obstacle is any item or collection of loose debris (such as stones, leaves, twigs, or unconnected branches), or any item as designated by the Director.
2. A player may request that other people move themselves or their belongings.
3. A player may restore course equipment to its proper working order, including the removal of obstacles.
Which of the 1, 2, or 3 numbered exceptions do you think would allow a player to intentionally knock snow off a branch? It would have to be #1 right? Because #2 is about people and belongings, and #3 is about course equipment.
And #1 refers to the playing surface...a branch in the air is not a playing surface.
So it's very clear that 803.01B does not allow you to move the snow, because it references "any obstacle on the course"...so for it to be legal one would need to find a specific rule that DOES allow for it in order to contradict that wide-spanning rule against it.