Russian Zelda player Пекарь Юсоновэбич has figured out yet another cool trick that everyone can screw around with -- turbo surfing. Basically you take a minecart, put it on a raft, and use magnesis to quickly jolt the latter.
This isn't nearly as fast (and the water system isn't nearly as vast) as Wind Waker HD's "Superswimming" mechanic, but it gets the job done. I wonder how a lot of these "all Divine Beast" runs will go with all these tricks. At the moment everyone is racing for an "any %" clear, but other categories will probably open up soon enough.
Be warned -- this isn't a silent Let's Play, and the dude yells quite a bit.