Interesting, I was unaware of that one.

I’ll look more into it later, learn about its failure modes and whatnot, but off the top of my head, it seems like it would still be a less effective system. I think I would much rather have one axle working. That mitigates the case where the two wheels are on different frictional surfaces, which could leave you with just a single wheel braking.

And still, if the fluid reservoir is a single undivided container, I’m not able to imagine a case where two wheels - horizontal or diagonal - would fail at once.