Standing on a chest does not allow the player to walk through a 2 high path

If the player stands on a chest, whether in Creative or Survival, it does not allow the player to walk through a path that is 2 high. ie as if the player was walking on layered snow

To Recreate:
the chest must be the block under your feet

It is as if the chest is having the soulsand effect on passing trough only 2 high passages.