No! As the honeycomb in the super is being rotated in the same vertical plane that it sits in while the hive is closed, uncapped honey won't leak out when the hive is opened using the Super Lifter.
Honey doesn't leak from uncapped comb because the hexagonal cells are facing sideways. The honey is viscous (it's thick and doesn't flow easily) and surface tension causes it to stick to the cell walls.
Many beekeepers already rotate the super like this so that it can be put down on its end during a brood inspection - we've been doing it that way in the Flow apiary for years!
