Video was too large, so I have this link for video evidence. A copy of the world is also attached for testing purposes

When moving up and down on the edge of a scaffold, different movement is experienced depending on the direction. 

• Downward movement seems to be much faster than descending the center of a scaffold, and the game seems to consider it as a freefall 
  • Fall damage does happen when abruptly stopping on the scaffold  
  • Falling/jumping  off the scaffold, but then colliding back into it does cause fall damage (may be working as intended)
  • Because it seems to be considered a freefall, water does negate any fall damage
• Upward movement is segmented as the player jumping up every scaffold block
  • The player is not affected by fall damage when moving up the edges of the scaffold
  • The player is hindered by other scaffolding blocks beside the scaffold they are traversing (not included in video)

I do use an alternative texture for scaffolds to make the center transparent. This should have no effect on duplicating the bug.