The Bug

When riding a pig with carrot on a stick in hand, the vertical momentum retained upon bouncing off of slime blocks from a height is less than a player, unridden pig, or pig that is being ridden without a carrot on a stick's retained vertical height.

Expected Behavior
If you have a carrot on a stick in hand, you should bounce up as high as any instance in which you don't and are falling from the same height.

Observed Behavior
You don't bounce up as high as other instances.

It should be noted that in both cases fall damage on a non-slime block block is the same as otherwise, but the momentum off of a slime block changes. I tested this in a large chamber of at least 50 blocks of height with a slime block floor in most instances. In regard to fall damage taken I used attributes to increase each pig's maximum health. This has been tested in both a multiplayer and single player world.