Moving and jumping on slippery surfaces provides additional forward momentum, allowing faster-than-sprinting movement

You can (almost) infinitely build up speed via a slippery road with solid blocks 3 blocks above them (ice tunnels), because of the momentum boost when jumping and moving.

Realistically jumping and running on ice should not be easy; but gameplay above realism; the momentum boost should just be removed when jumping while on a slippery surface, to prevent the speed buildup on such roads.