When placing a bottom half slab on a honey block, and then jumping on top of said slab, it prevents the player from jumping the same way when a player jumps on top of a honey block.

When walking on top of slabs placed on top of slime blocks, the player has the same momentum as if it was walking without slabs in between. falling on top of said slab makes the player have fall damage and doesn't bounce back, so not all proprieties are applied.

Also tested if slabs on soul soil would activate soul speed and indeed it does.