What I expected to happen
Was that I would be pushed off even while sneaking.

What Happened
Was that I got pushed to the side of the block as far as sneaking allowed and were able to stand there with no problems.
See example in Image 1

How to replicate
See image 2
1. Build it
2. stand in the lowest block (grass block)
3. hold sneak
4. break block above you (the dirt with sand above it)
5. do NOT move.