Steps to reproduce

1. Build 4 water-on-ice streams around the outside of a square of non-ice solid-top blocks, like this:
2. Drop items in the stream on each side.

Expected results

After being aligned by one of the anvils, items go around and around the build, sliding on the ice.

Actual results

On the north and west sides, items slow down and fail to cross from the end of the stream to the next anvil.

Items have an inconsistent speed when traveling between blue ice and another block, based on which direction they're traveling in.

If you are trying to, for example, make a sorting system where you want hoppers to be able to pick up an item while still having the speed of blue ice, it's common to center the item between the hoppers and ice to achieve these results. This works perfectly in the south and east directions, but is inconsistent in the north and west.

In the north and west, the items gain no speed from the ice, which consequently breaks many contraptions.

To reproduce this bug, place a square of blue ice, with a smaller square of solid blocks directly inside of the ice at the same height. Add buttons to the top of the solid blocks and an outside ring of blocks, one block higher, to prevent water from spilling out. Then place an anvil in each corner with its long sides being parallel to the direction you want the water to go. It's orientation is important. From there waterlog the anvils and place buttons to prevent the water from going in the wrong direction. Please refer to the attached image for questions.

When tossing items into the water streams, you'll find that in the south and eastern directions they quickly move, while in the north and east they're not affected by the ice at all.

The second image attached is a practical application where this bug comes into play. It's a super smelter, and although the two sides are mirrored, the right side of the image doesn't work because of this inconsistency. This is the second large scale smelter I've designed, with the first one being broken by a hopper minecart bug. It would be really great if this was fixed so I wouldn't have to figure out how to design another one without water streams or hopper minecarts. Thank you.