I have heard from many that when I fly (while host) on a Cube (only a cube somehow) and I break it by gently lowering my hand (to be "falling" on it and break it), The Client Side person will see a Cube where it broke. They can fall on top of it to get rid of it. Sometimes Client can't walk through it and sometimes they can. Other blocks are unaffected.

Recreate: (as Host)

1:Fly on Cube (don't move except slightly up)

2:Lower hand to be Falling and break Cube

3:Client Side Person should see a Cube in the air at that spot.